Network Working Group                                   A. Phillips, Ed.
Request for Comments: 5646                                        Lab126
BCP: 47                                                    M. Davis, Ed.
Obsoletes: 4646                                                   Google
Category: Best Current Practice                           September 2009
Network Working Group                                   A. Phillips, Ed.
Request for Comments: 5646                                        Lab126
BCP: 47                                                    M. Davis, Ed.
Obsoletes: 4646                                                   Google
Category: Best Current Practice                           September 2009

Tags for Identifying Languages




This document describes the structure, content, construction, and semantics of language tags for use in cases where it is desirable to indicate the language used in an information object. It also describes how to register values for use in language tags and the creation of user-defined extensions for private interchange.


Status of This Memo


This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. Distribution of this memo is unlimited.


Copyright Notice


Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved.

版权所有(c)2009 IETF信托基金和确定为文件作者的人员。版权所有。

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date of publication of this document ( Please review these documents carefully, as they describe your rights and restrictions with respect to this document.

本文件受BCP 78和IETF信托在本文件出版之日生效的与IETF文件有关的法律规定的约束( 请仔细阅读这些文件,因为它们描述了您对本文件的权利和限制。

This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.


Table of Contents


   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  The Language Tag . . . . . . . . . . . . . . . . . . . . . . .  4
     2.1.  Syntax . . . . . . . . . . . . . . . . . . . . . . . . . .  4
       2.1.1.  Formatting of Language Tags  . . . . . . . . . . . . .  6
     2.2.  Language Subtag Sources and Interpretation . . . . . . . .  8
       2.2.1.  Primary Language Subtag . . . . . . . . . . . . . . . . 9
       2.2.2.  Extended Language Subtags  . . . . . . . . . . . . . . 11
       2.2.3.  Script Subtag  . . . . . . . . . . . . . . . . . . . . 12
       2.2.4.  Region Subtag  . . . . . . . . . . . . . . . . . . . . 13
       2.2.5.  Variant Subtags  . . . . . . . . . . . . . . . . . . . 15
       2.2.6.  Extension Subtags  . . . . . . . . . . . . . . . . . . 16
       2.2.7.  Private Use Subtags  . . . . . . . . . . . . . . . . . 18
       2.2.8.  Grandfathered and Redundant Registrations  . . . . . . 18
       2.2.9.  Classes of Conformance . . . . . . . . . . . . . . . . 19
   3.  Registry Format and Maintenance  . . . . . . . . . . . . . . . 21
     3.1.  Format of the IANA Language Subtag Registry  . . . . . . . 21
       3.1.1.  File Format  . . . . . . . . . . . . . . . . . . . . . 21
       3.1.2.  Record and Field Definitions . . . . . . . . . . . . . 23
       3.1.3.  Type Field . . . . . . . . . . . . . . . . . . . . . . 26
       3.1.4.  Subtag and Tag Fields  . . . . . . . . . . . . . . . . 26
       3.1.5.  Description Field  . . . . . . . . . . . . . . . . . . 26
       3.1.6.  Deprecated Field . . . . . . . . . . . . . . . . . . . 28
       3.1.7.  Preferred-Value Field  . . . . . . . . . . . . . . . . 28
       3.1.8.  Prefix Field . . . . . . . . . . . . . . . . . . . . . 31
       3.1.9.  Suppress-Script Field  . . . . . . . . . . . . . . . . 32
       3.1.10. Macrolanguage Field  . . . . . . . . . . . . . . . . . 32
       3.1.11. Scope Field  . . . . . . . . . . . . . . . . . . . . . 33
       3.1.12. Comments Field . . . . . . . . . . . . . . . . . . . . 34
     3.2.  Language Subtag Reviewer . . . . . . . . . . . . . . . . . 35
     3.3.  Maintenance of the Registry  . . . . . . . . . . . . . . . 35
     3.4.  Stability of IANA Registry Entries . . . . . . . . . . . . 36
     3.5.  Registration Procedure for Subtags . . . . . . . . . . . . 41
     3.6.  Possibilities for Registration . . . . . . . . . . . . . . 46
     3.7.  Extensions and the Extensions Registry . . . . . . . . . . 49
     3.8.  Update of the Language Subtag Registry . . . . . . . . . . 52
     3.9.  Applicability of the Subtag Registry . . . . . . . . . . . 52
   4.  Formation and Processing of Language Tags  . . . . . . . . . . 53
     4.1.  Choice of Language Tag . . . . . . . . . . . . . . . . . . 53
       4.1.1.  Tagging Encompassed Languages  . . . . . . . . . . . . 58
       4.1.2.  Using Extended Language Subtags  . . . . . . . . . . . 59
     4.2.  Meaning of the Language Tag  . . . . . . . . . . . . . . . 61
     4.3.  Lists of Languages . . . . . . . . . . . . . . . . . . . . 63
     4.4.  Length Considerations  . . . . . . . . . . . . . . . . . . 63
       4.4.1.  Working with Limited Buffer Sizes  . . . . . . . . . . 64
       4.4.2.  Truncation of Language Tags  . . . . . . . . . . . . . 65
     4.5.  Canonicalization of Language Tags  . . . . . . . . . . . . 66
   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  The Language Tag . . . . . . . . . . . . . . . . . . . . . . .  4
     2.1.  Syntax . . . . . . . . . . . . . . . . . . . . . . . . . .  4
       2.1.1.  Formatting of Language Tags  . . . . . . . . . . . . .  6
     2.2.  Language Subtag Sources and Interpretation . . . . . . . .  8
       2.2.1.  Primary Language Subtag . . . . . . . . . . . . . . . . 9
       2.2.2.  Extended Language Subtags  . . . . . . . . . . . . . . 11
       2.2.3.  Script Subtag  . . . . . . . . . . . . . . . . . . . . 12
       2.2.4.  Region Subtag  . . . . . . . . . . . . . . . . . . . . 13
       2.2.5.  Variant Subtags  . . . . . . . . . . . . . . . . . . . 15
       2.2.6.  Extension Subtags  . . . . . . . . . . . . . . . . . . 16
       2.2.7.  Private Use Subtags  . . . . . . . . . . . . . . . . . 18
       2.2.8.  Grandfathered and Redundant Registrations  . . . . . . 18
       2.2.9.  Classes of Conformance . . . . . . . . . . . . . . . . 19
   3.  Registry Format and Maintenance  . . . . . . . . . . . . . . . 21
     3.1.  Format of the IANA Language Subtag Registry  . . . . . . . 21
       3.1.1.  File Format  . . . . . . . . . . . . . . . . . . . . . 21
       3.1.2.  Record and Field Definitions . . . . . . . . . . . . . 23
       3.1.3.  Type Field . . . . . . . . . . . . . . . . . . . . . . 26
       3.1.4.  Subtag and Tag Fields  . . . . . . . . . . . . . . . . 26
       3.1.5.  Description Field  . . . . . . . . . . . . . . . . . . 26
       3.1.6.  Deprecated Field . . . . . . . . . . . . . . . . . . . 28
       3.1.7.  Preferred-Value Field  . . . . . . . . . . . . . . . . 28
       3.1.8.  Prefix Field . . . . . . . . . . . . . . . . . . . . . 31
       3.1.9.  Suppress-Script Field  . . . . . . . . . . . . . . . . 32
       3.1.10. Macrolanguage Field  . . . . . . . . . . . . . . . . . 32
       3.1.11. Scope Field  . . . . . . . . . . . . . . . . . . . . . 33
       3.1.12. Comments Field . . . . . . . . . . . . . . . . . . . . 34
     3.2.  Language Subtag Reviewer . . . . . . . . . . . . . . . . . 35
     3.3.  Maintenance of the Registry  . . . . . . . . . . . . . . . 35
     3.4.  Stability of IANA Registry Entries . . . . . . . . . . . . 36
     3.5.  Registration Procedure for Subtags . . . . . . . . . . . . 41
     3.6.  Possibilities for Registration . . . . . . . . . . . . . . 46
     3.7.  Extensions and the Extensions Registry . . . . . . . . . . 49
     3.8.  Update of the Language Subtag Registry . . . . . . . . . . 52
     3.9.  Applicability of the Subtag Registry . . . . . . . . . . . 52
   4.  Formation and Processing of Language Tags  . . . . . . . . . . 53
     4.1.  Choice of Language Tag . . . . . . . . . . . . . . . . . . 53
       4.1.1.  Tagging Encompassed Languages  . . . . . . . . . . . . 58
       4.1.2.  Using Extended Language Subtags  . . . . . . . . . . . 59
     4.2.  Meaning of the Language Tag  . . . . . . . . . . . . . . . 61
     4.3.  Lists of Languages . . . . . . . . . . . . . . . . . . . . 63
     4.4.  Length Considerations  . . . . . . . . . . . . . . . . . . 63
       4.4.1.  Working with Limited Buffer Sizes  . . . . . . . . . . 64
       4.4.2.  Truncation of Language Tags  . . . . . . . . . . . . . 65
     4.5.  Canonicalization of Language Tags  . . . . . . . . . . . . 66
     4.6.  Considerations for Private Use Subtags . . . . . . . . . . 68
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 69
     5.1.  Language Subtag Registry . . . . . . . . . . . . . . . . . 69
     5.2.  Extensions Registry  . . . . . . . . . . . . . . . . . . . 71
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 71
   7.  Character Set Considerations . . . . . . . . . . . . . . . . . 72
   8.  Changes from RFC 4646  . . . . . . . . . . . . . . . . . . . . 73
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 76
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 76
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 78
   Appendix A.  Examples of Language Tags (Informative) . . . . . . . 80
   Appendix B.  Examples of Registration Forms  . . . . . . . . . . . 82
   Appendix C.  Acknowledgements  . . . . . . . . . . . . . . . . . . 83
     4.6.  Considerations for Private Use Subtags . . . . . . . . . . 68
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 69
     5.1.  Language Subtag Registry . . . . . . . . . . . . . . . . . 69
     5.2.  Extensions Registry  . . . . . . . . . . . . . . . . . . . 71
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 71
   7.  Character Set Considerations . . . . . . . . . . . . . . . . . 72
   8.  Changes from RFC 4646  . . . . . . . . . . . . . . . . . . . . 73
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 76
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 76
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 78
   Appendix A.  Examples of Language Tags (Informative) . . . . . . . 80
   Appendix B.  Examples of Registration Forms  . . . . . . . . . . . 82
   Appendix C.  Acknowledgements  . . . . . . . . . . . . . . . . . . 83
1. Introduction
1. 介绍

Human beings on our planet have, past and present, used a number of languages. There are many reasons why one would want to identify the language used when presenting or requesting information.


The language of an information item or a user's language preferences often need to be identified so that appropriate processing can be applied. For example, the user's language preferences in a Web browser can be used to select Web pages appropriately. Language information can also be used to select among tools (such as dictionaries) to assist in the processing or understanding of content in different languages. Knowledge about the particular language used by some piece of information content might be useful or even required by some types of processing, for example, spell-checking, computer-synthesized speech, Braille transcription, or high-quality print renderings.


One means of indicating the language used is by labeling the information content with an identifier or "tag". These tags can also be used to specify the user's preferences when selecting information content or to label additional attributes of content and associated resources.


Sometimes language tags are used to indicate additional language attributes of content. For example, indicating specific information about the dialect, writing system, or orthography used in a document or resource may enable the user to obtain information in a form that they can understand, or it can be important in processing or rendering the given content into an appropriate form or style.


This document specifies a particular identifier mechanism (the language tag) and a registration function for values to be used to


form tags. It also defines a mechanism for private use values and future extensions.


This document replaces [RFC4646] (which obsoleted [RFC3066] which, in turn, replaced [RFC1766]). This document, in combination with [RFC4647], comprises BCP 47. For a list of changes in this document, see Section 8.

本文件取代了[RFC4646](该文件淘汰了[RFC3066],而后者又取代了[RFC1766])。本文件与[RFC4647]一起构成BCP 47。有关本文件中的变更列表,请参见第8节。

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].


2. The Language Tag
2. 语言标签

Language tags are used to help identify languages, whether spoken, written, signed, or otherwise signaled, for the purpose of communication. This includes constructed and artificial languages but excludes languages not intended primarily for human communication, such as programming languages.


2.1. Syntax
2.1. 语法

A language tag is composed from a sequence of one or more "subtags", each of which refines or narrows the range of language identified by the overall tag. Subtags, in turn, are a sequence of alphanumeric characters (letters and digits), distinguished and separated from other subtags in a tag by a hyphen ("-", [Unicode] U+002D).


There are different types of subtag, each of which is distinguished by length, position in the tag, and content: each subtag's type can be recognized solely by these features. This makes it possible to extract and assign some semantic information to the subtags, even if the specific subtag values are not recognized. Thus, a language tag processor need not have a list of valid tags or subtags (that is, a copy of some version of the IANA Language Subtag Registry) in order to perform common searching and matching operations. The only exceptions to this ability to infer meaning from subtag structure are the grandfathered tags listed in the productions 'regular' and 'irregular' below. These tags were registered under [RFC3066] and are a fixed list that can never change.


The syntax of the language tag in ABNF [RFC5234] is:


 Language-Tag  = langtag             ; normal language tags
               / privateuse          ; private use tag
               / grandfathered       ; grandfathered tags
 Language-Tag  = langtag             ; normal language tags
               / privateuse          ; private use tag
               / grandfathered       ; grandfathered tags
 langtag       = language
                 ["-" script]
                 ["-" region]
                 *("-" variant)
                 *("-" extension)
                 ["-" privateuse]
 langtag       = language
                 ["-" script]
                 ["-" region]
                 *("-" variant)
                 *("-" extension)
                 ["-" privateuse]
 language      = 2*3ALPHA            ; shortest ISO 639 code
                 ["-" extlang]       ; sometimes followed by
                                     ; extended language subtags
               / 4ALPHA              ; or reserved for future use
               / 5*8ALPHA            ; or registered language subtag
 language      = 2*3ALPHA            ; shortest ISO 639 code
                 ["-" extlang]       ; sometimes followed by
                                     ; extended language subtags
               / 4ALPHA              ; or reserved for future use
               / 5*8ALPHA            ; or registered language subtag
 extlang       = 3ALPHA              ; selected ISO 639 codes
                 *2("-" 3ALPHA)      ; permanently reserved
 extlang       = 3ALPHA              ; selected ISO 639 codes
                 *2("-" 3ALPHA)      ; permanently reserved

script = 4ALPHA ; ISO 15924 code

脚本=4ALPHA;ISO 15924代码

 region        = 2ALPHA              ; ISO 3166-1 code
               / 3DIGIT              ; UN M.49 code
 region        = 2ALPHA              ; ISO 3166-1 code
               / 3DIGIT              ; UN M.49 code
 variant       = 5*8alphanum         ; registered variants
               / (DIGIT 3alphanum)
 variant       = 5*8alphanum         ; registered variants
               / (DIGIT 3alphanum)
 extension     = singleton 1*("-" (2*8alphanum))
 extension     = singleton 1*("-" (2*8alphanum))
                                     ; Single alphanumerics
                                     ; "x" reserved for private use
 singleton     = DIGIT               ; 0 - 9
               / %x41-57             ; A - W
               / %x59-5A             ; Y - Z
               / %x61-77             ; a - w
               / %x79-7A             ; y - z
                                     ; Single alphanumerics
                                     ; "x" reserved for private use
 singleton     = DIGIT               ; 0 - 9
               / %x41-57             ; A - W
               / %x59-5A             ; Y - Z
               / %x61-77             ; a - w
               / %x79-7A             ; y - z
 privateuse    = "x" 1*("-" (1*8alphanum))
 privateuse    = "x" 1*("-" (1*8alphanum))
 grandfathered = irregular           ; non-redundant tags registered
               / regular             ; during the RFC 3066 era
 grandfathered = irregular           ; non-redundant tags registered
               / regular             ; during the RFC 3066 era
 irregular     = "en-GB-oed"         ; irregular tags do not match
               / "i-ami"             ; the 'langtag' production and
               / "i-bnn"             ; would not otherwise be
               / "i-default"         ; considered 'well-formed'
               / "i-enochian"        ; These tags are all valid,
               / "i-hak"             ; but most are deprecated
               / "i-klingon"         ; in favor of more modern
               / "i-lux"             ; subtags or subtag
               / "i-mingo"           ; combination
 irregular     = "en-GB-oed"         ; irregular tags do not match
               / "i-ami"             ; the 'langtag' production and
               / "i-bnn"             ; would not otherwise be
               / "i-default"         ; considered 'well-formed'
               / "i-enochian"        ; These tags are all valid,
               / "i-hak"             ; but most are deprecated
               / "i-klingon"         ; in favor of more modern
               / "i-lux"             ; subtags or subtag
               / "i-mingo"           ; combination
               / "i-navajo"
               / "i-pwn"
               / "i-tao"
               / "i-tay"
               / "i-tsu"
               / "sgn-BE-FR"
               / "sgn-BE-NL"
               / "sgn-CH-DE"
               / "i-navajo"
               / "i-pwn"
               / "i-tao"
               / "i-tay"
               / "i-tsu"
               / "sgn-BE-FR"
               / "sgn-BE-NL"
               / "sgn-CH-DE"
 regular       = "art-lojban"        ; these tags match the 'langtag'
               / "cel-gaulish"       ; production, but their subtags
               / "no-bok"            ; are not extended language
               / "no-nyn"            ; or variant subtags: their meaning
               / "zh-guoyu"          ; is defined by their registration
               / "zh-hakka"          ; and all of these are deprecated
               / "zh-min"            ; in favor of a more modern
               / "zh-min-nan"        ; subtag or sequence of subtags
               / "zh-xiang"
 regular       = "art-lojban"        ; these tags match the 'langtag'
               / "cel-gaulish"       ; production, but their subtags
               / "no-bok"            ; are not extended language
               / "no-nyn"            ; or variant subtags: their meaning
               / "zh-guoyu"          ; is defined by their registration
               / "zh-hakka"          ; and all of these are deprecated
               / "zh-min"            ; in favor of a more modern
               / "zh-min-nan"        ; subtag or sequence of subtags
               / "zh-xiang"
 alphanum      = (ALPHA / DIGIT)     ; letters and numbers
 alphanum      = (ALPHA / DIGIT)     ; letters and numbers

Figure 1: Language Tag ABNF


For examples of language tags, see Appendix A.


All subtags have a maximum length of eight characters. Whitespace is not permitted in a language tag. There is a subtlety in the ABNF production 'variant': a variant starting with a digit has a minimum length of four characters, while those starting with a letter have a minimum length of five characters.


Although [RFC5234] refers to octets, the language tags described in this document are sequences of characters from the US-ASCII [ISO646] repertoire. Language tags MAY be used in documents and applications that use other encodings, so long as these encompass the relevant part of the US-ASCII repertoire. An example of this would be an XML document that uses the UTF-16LE [RFC2781] encoding of [Unicode].


2.1.1. Formatting of Language Tags
2.1.1. 语言标记的格式

At all times, language tags and their subtags, including private use and extensions, are to be treated as case insensitive: there exist conventions for the capitalization of some of the subtags, but these MUST NOT be taken to carry meaning.


Thus, the tag "mn-Cyrl-MN" is not distinct from "MN-cYRL-mn" or "mN-cYrL-Mn" (or any other combination), and each of these variations


conveys the same meaning: Mongolian written in the Cyrillic script as used in Mongolia.


The ABNF syntax also does not distinguish between upper- and lowercase: the uppercase US-ASCII letters in the range 'A' through 'Z' are always considered equivalent and mapped directly to their US-ASCII lowercase equivalents in the range 'a' through 'z'. So the tag "I-AMI" is considered equivalent to that value "i-ami" in the 'irregular' production.


Although case distinctions do not carry meaning in language tags, consistent formatting and presentation of language tags will aid users. The format of subtags in the registry is RECOMMENDED as the form to use in language tags. This format generally corresponds to the common conventions for the various ISO standards from which the subtags are derived.


These conventions include:


o [ISO639-1] recommends that language codes be written in lowercase ('mn' Mongolian).

o [ISO639-1]建议语言代码应使用小写(“mn”蒙古语)。

o [ISO15924] recommends that script codes use lowercase with the initial letter capitalized ('Cyrl' Cyrillic).

o [ISO15924]建议脚本代码使用小写字母,首字母大写(“Cyrl”西里尔字母)。

o [ISO3166-1] recommends that country codes be capitalized ('MN' Mongolia).

o [ISO3166-1]建议国家代码大写(“MN”蒙古)。

An implementation can reproduce this format without accessing the registry as follows. All subtags, including extension and private use subtags, use lowercase letters with two exceptions: two-letter and four-letter subtags that neither appear at the start of the tag nor occur after singletons. Such two-letter subtags are all uppercase (as in the tags "en-CA-x-ca" or "sgn-BE-FR") and four-letter subtags are titlecase (as in the tag "az-Latn-x-latn").


Note: Case folding of ASCII letters in certain locales, unless carefully handled, sometimes produces non-ASCII character values. The Unicode Character Database file "SpecialCasing.txt" [SpecialCasing] defines the specific cases that are known to cause problems with this. In particular, the letter 'i' (U+0069) in Turkish and Azerbaijani is uppercased to U+0130 (LATIN CAPITAL LETTER I WITH DOT ABOVE). Implementers SHOULD specify a locale-neutral casing operation to ensure that case folding of subtags does not produce this value, which is illegal in language tags. For example, if one were to uppercase the region subtag 'in' using Turkish locale rules, the sequence U+0130 U+004E would result, instead of the expected 'IN'.


2.2. Language Subtag Sources and Interpretation
2.2. 语言子标记来源与解释

The namespace of language tags and their subtags is administered by the Internet Assigned Numbers Authority (IANA) according to the rules in Section 5 of this document. The Language Subtag Registry maintained by IANA is the source for valid subtags: other standards referenced in this section provide the source material for that registry.


Terminology used in this document:


o "Tag" refers to a complete language tag, such as "sr-Latn-RS" or "az-Arab-IR". Examples of tags in this document are enclosed in double-quotes ("en-US").

o “Tag”指完整的语言标签,如“sr Latn RS”或“az Arab IR”。本文件中的标签示例附在双引号(“en US”)中。

o "Subtag" refers to a specific section of a tag, delimited by a hyphen, such as the subtags 'zh', 'Hant', and 'CN' in the tag "zh-Hant-CN". Examples of subtags in this document are enclosed in single quotes ('Hant').

o “Subtag”是指标记的特定部分,由连字符分隔,例如标记“zh Hant CN”中的子标记“zh”、“Hant”和“CN”。本文件中的子标签示例附在单引号(“Hant”)中。

o "Code" refers to values defined in external standards (and that are used as subtags in this document). For example, 'Hant' is an [ISO15924] script code that was used to define the 'Hant' script subtag for use in a language tag. Examples of codes in this document are enclosed in single quotes ('en', 'Hant').

o “代码”是指外部标准中定义的值(在本文件中用作子标签)。例如,“Hant”是一个[ISO15924]脚本代码,用于定义语言标记中使用的“Hant”脚本子标记。本文件中的代码示例附在单引号中(“en”、“Hant”)。

Language tags are designed so that each subtag type has unique length and content restrictions. These make identification of the subtag's type possible, even if the content of the subtag itself is unrecognized. This allows tags to be parsed and processed without reference to the latest version of the underlying standards or the IANA registry and makes the associated exception handling when parsing tags simpler.


Some of the subtags in the IANA registry do not come from an underlying standard. These can only appear in specific positions in a tag: they can only occur as primary language subtags or as variant subtags.


Sequences of private use and extension subtags MUST occur at the end of the sequence of subtags and MUST NOT be interspersed with subtags defined elsewhere in this document. These sequences are introduced by single-character subtags, which are reserved as follows:


o The single-letter subtag 'x' introduces a sequence of private use subtags. The interpretation of any private use subtag is defined

o 单字母子标签“x”引入了一系列专用子标签。定义了任何专用子标签的解释

solely by private agreement and is not defined by the rules in this section or in any standard or registry defined in this document.


o The single-letter subtag 'i' is used by some grandfathered tags, such as "i-default", where it always appears in the first position and cannot be confused with an extension.

o 单字母子标记“i”由一些祖父标记使用,例如“i-default”,它总是出现在第一个位置,不能与扩展混淆。

o All other single-letter and single-digit subtags are reserved to introduce standardized extension subtag sequences as described in Section 3.7.

o 保留所有其他单字母和单数字子标签,以引入第3.7节所述的标准化扩展子标签序列。

2.2.1. Primary Language Subtag
2.2.1. 初级语言子标签

The primary language subtag is the first subtag in a language tag and cannot be omitted, with two exceptions:


o The single-character subtag 'x' as the primary subtag indicates that the language tag consists solely of subtags whose meaning is defined by private agreement. For example, in the tag "x-fr-CH", the subtags 'fr' and 'CH' do not represent the French language or the country of Switzerland (or any other value in the IANA registry) unless there is a private agreement in place to do so. See Section 4.6.

o 作为主要子标记的单字符子标记“x”表示语言标记仅由子标记组成,其含义由私人协议定义。例如,在标签“x-fr-CH”中,子标签“fr”和“CH”不代表法语或瑞士国家(或IANA注册表中的任何其他值),除非存在这样做的私人协议。见第4.6节。

o The single-character subtag 'i' is used by some grandfathered tags (see Section 2.2.8) such as "i-klingon" and "i-bnn". (Other grandfathered tags have a primary language subtag in their first position.)

o 单字符子标签“i”由一些祖父标记(见第2.2.8节)使用,如“i-klingon”和“i-bnn”。(其他grandfathered标记的第一个位置有一个primary language子标记。)

The following rules apply to the primary language subtag:


1. Two-character primary language subtags were defined in the IANA registry according to the assignments found in the standard "ISO 639-1:2002, Codes for the representation of names of languages -- Part 1: Alpha-2 code" [ISO639-1], or using assignments subsequently made by the ISO 639-1 registration authority (RA) or governing standardization bodies.

1. IANA注册中心根据标准“ISO 639-1:2002,语言名称表示代码——第1部分:Alpha-2代码”[ISO639-1]中的分配,或使用ISO 639-1注册机构(RA)或管理标准化机构随后进行的分配,定义了两个字符的主要语言子标签。

2. Three-character primary language subtags in the IANA registry were defined according to the assignments found in one of these additional ISO 639 parts or assignments subsequently made by the relevant ISO 639 registration authorities or governing standardization bodies:

2. IANA注册表中的三个字符主要语言子标签是根据这些额外ISO 639部分中的一个部分中的分配或相关ISO 639注册机构或管理标准化机构随后进行的分配定义的:

       A.  "ISO 639-2:1998 - Codes for the representation of names of
           languages -- Part 2: Alpha-3 code - edition 1" [ISO639-2]
       A.  "ISO 639-2:1998 - Codes for the representation of names of
           languages -- Part 2: Alpha-3 code - edition 1" [ISO639-2]

B. "ISO 639-3:2007 - Codes for the representation of names of languages -- Part 3: Alpha-3 code for comprehensive coverage of languages" [ISO639-3]

B.“ISO 639-3:2007——语言名称表示代码——第3部分:语言全面覆盖阿尔法-3代码”[ISO639-3]

C. "ISO 639-5:2008 - Codes for the representation of names of languages -- Part 5: Alpha-3 code for language families and groups" [ISO639-5]

C.“ISO 639-5:2008——语言名称表示代码——第5部分:语系和语组的Alpha-3代码”[ISO639-5]

3. The subtags in the range 'qaa' through 'qtz' are reserved for private use in language tags. These subtags correspond to codes reserved by ISO 639-2 for private use. These codes MAY be used for non-registered primary language subtags (instead of using private use subtags following 'x-'). Please refer to Section 4.6 for more information on private use subtags.

3. “qaa”到“qtz”范围内的子标签在语言标签中保留供私人使用。这些子标签对应于ISO 639-2保留供私人使用的代码。这些代码可用于未注册的主语言子标记(而不是使用“x-”后面的专用子标记)。有关专用子标签的更多信息,请参阅第4.6节。

4. Four-character language subtags are reserved for possible future standardization.

4. 保留了四个字符的语言子标签,以便将来可能实现标准化。

5. Any language subtags of five to eight characters in length in the IANA registry were defined via the registration process in Section 3.5 and MAY be used to form the primary language subtag. An example of what such a registration might include is the grandfathered IANA registration "i-enochian". The subtag 'enochian' could be registered in the IANA registry as a primary language subtag (assuming that ISO 639 does not register this language first), making tags such as "enochian-AQ" and "enochian-Latn" valid.

5. IANA注册表中长度为5到8个字符的任何语言子标签都是通过第3.5节中的注册过程定义的,可用于构成主语言子标签。这种注册可能包括的一个例子是祖辈IANA注册“i-enochian”。子标签“enochian”可以在IANA注册中心注册为主要语言子标签(假设ISO 639没有首先注册该语言),使“enochian AQ”和“enochian Latn”等标签有效。

At the time this document was created, there were no examples of this kind of subtag. Future registrations of this type are discouraged: an attempt to register any new proposed primary language MUST be made to the ISO 639 registration authority. Proposals rejected by the ISO 639 registration authority are unlikely to meet the criteria for primary language subtags and are thus unlikely to be registered.

在创建此文档时,没有此类子标签的示例。不鼓励将来注册这种类型的语言:必须向ISO 639注册机构申请注册任何新的主语言。被ISO 639注册机构拒绝的提案不太可能满足主要语言子标签的标准,因此不太可能被注册。

6. Other values MUST NOT be assigned to the primary subtag except by revision or update of this document.

6. 除非通过修订或更新本文件,否则不得将其他值分配给主子标签。

When languages have both an ISO 639-1 two-character code and a three-character code (assigned by ISO 639-2, ISO 639-3, or ISO 639-5), only the ISO 639-1 two-character code is defined in the IANA registry.

当语言同时具有ISO 639-1双字符代码和三字符代码(由ISO 639-2、ISO 639-3或ISO 639-5指定)时,IANA注册表中仅定义ISO 639-1双字符代码。

When a language has no ISO 639-1 two-character code and the ISO 639-2/T (Terminology) code and the ISO 639-2/B (Bibliographic) code for that language differ, only the Terminology code is defined in the IANA registry. At the time this document was created, all languages that had both kinds of three-character codes were also assigned a

当一种语言没有ISO 639-1双字符代码且该语言的ISO 639-2/T(术语)代码和ISO 639-2/B(书目)代码不同时,IANA注册表中仅定义术语代码。在创建此文档时,同时具有两种三字符代码的所有语言也被分配了一个

two-character code; it is expected that future assignments of this nature will not occur.


In order to avoid instability in the canonical form of tags, if a two-character code is added to ISO 639-1 for a language for which a three-character code was already included in either ISO 639-2 or ISO 639-3, the two-character code MUST NOT be registered. See Section 3.4.

为了避免标签规范形式的不稳定性,如果在ISO 639-1中添加了两个字符的代码,而ISO 639-2或ISO 639-3中已经包含了三个字符的代码,则不得注册两个字符的代码。见第3.4节。

For example, if some content were tagged with 'haw' (Hawaiian), which currently has no two-character code, the tag would not need to be changed if ISO 639-1 were to assign a two-character code to the Hawaiian language at a later date.

例如,如果某些内容被标记为“haw”(夏威夷语),目前没有两个字符的代码,则如果ISO 639-1在以后将两个字符的代码分配给夏威夷语,则不需要更改标记。

To avoid these problems with versioning and subtag choice (as experienced during the transition between RFC 1766 and RFC 3066), as well as to ensure the canonical nature of subtags defined by this document, the ISO 639 Registration Authority Joint Advisory Committee (ISO 639/RA-JAC) has included the following statement in [iso639.prin]:

为了避免版本控制和子标签选择方面的这些问题(如RFC 1766和RFC 3066之间的过渡期间所经历的),以及确保本文件定义的子标签的规范性,ISO 639注册机构联合咨询委员会(ISO 639/RA-JAC)在[iso639.prin]中包含以下声明:

"A language code already in ISO 639-2 at the point of freezing ISO 639-1 shall not later be added to ISO 639-1. This is to ensure consistency in usage over time, since users are directed in Internet applications to employ the alpha-3 code when an alpha-2 code for that language is not available."

“在ISO 639-1冻结时,ISO 639-2中已经存在的语言代码以后不得添加到ISO 639-1中。这是为了确保随着时间的推移使用的一致性,因为在互联网应用程序中,当该语言的alpha-2代码不可用时,用户被指示使用alpha-3代码。”

2.2.2. Extended Language Subtags
2.2.2. 扩展语言子标签

Extended language subtags are used to identify certain specially selected languages that, for various historical and compatibility reasons, are closely identified with or tagged using an existing primary language subtag. Extended language subtags are always used with their enclosing primary language subtag (indicated with a 'Prefix' field in the registry) when used to form the language tag. All languages that have an extended language subtag in the registry also have an identical primary language subtag record in the registry. This primary language subtag is RECOMMENDED for forming the language tag. The following rules apply to the extended language subtags:


1. Extended language subtags consist solely of three-letter subtags. All extended language subtag records defined in the registry were defined according to the assignments found in [ISO639-3]. Language collections and groupings, such as defined in [ISO639-5], are specifically excluded from being extended language subtags.

1. 扩展语言子标签仅由三个字母子标签组成。注册表中定义的所有扩展语言子标记记录都是根据[ISO639-3]中的赋值定义的。[ISO639-5]中定义的语言集合和分组被明确排除在扩展语言子标签之外。

2. Extended language subtag records MUST include exactly one 'Prefix' field indicating an appropriate subtag or sequence of subtags for that extended language subtag.

2. 扩展语言子标记记录必须仅包含一个“前缀”字段,指示该扩展语言子标记的适当子标记或子标记序列。

3. Extended language subtag records MUST include a 'Preferred-Value'. The 'Preferred-Value' and 'Subtag' fields MUST be identical.

3. 扩展语言子标记记录必须包含“首选值”。“首选值”和“子标记”字段必须相同。

4. Although the ABNF production 'extlang' permits up to three extended language tags in the language tag, extended language subtags MUST NOT include another extended language subtag in their 'Prefix'. That is, the second and third extended language subtag positions in a language tag are permanently reserved and tags that include those subtags in that position are, and will always remain, invalid.

4. 尽管ABNF产品“extlang”允许语言标记中最多有三个扩展语言标记,但扩展语言子标记的“前缀”中不得包含另一个扩展语言子标记。也就是说,语言标记中的第二个和第三个扩展语言子标记位置是永久保留的,并且在该位置包含这些子标记的标记是无效的,并且将始终保持无效。

For example, the macrolanguage Chinese ('zh') encompasses a number of languages. For compatibility reasons, each of these languages has both a primary and extended language subtag in the registry. A few selected examples of these include Gan Chinese ('gan'), Cantonese Chinese ('yue'), and Mandarin Chinese ('cmn'). Each is encompassed by the macrolanguage 'zh' (Chinese). Therefore, they each have the prefix "zh" in their registry records. Thus, Gan Chinese is represented with tags beginning "zh-gan" or "gan", Cantonese with tags beginning either "yue" or "zh-yue", and Mandarin Chinese with "zh-cmn" or "cmn". The language subtag 'zh' can still be used without an extended language subtag to label a resource as some unspecified variety of Chinese, while the primary language subtag ('gan', 'yue', 'cmn') is preferred to using the extended language form ("zh-gan", "zh-yue", "zh-cmn").


2.2.3. Script Subtag
2.2.3. 脚本子标签

Script subtags are used to indicate the script or writing system variations that distinguish the written forms of a language or its dialects. The following rules apply to the script subtags:


1. Script subtags MUST follow any primary and extended language subtags and MUST precede any other type of subtag.

1. 脚本子标记必须位于任何主语言子标记和扩展语言子标记之后,并且必须位于任何其他类型的子标记之前。

2. Script subtags consist of four letters and were defined according to the assignments found in [ISO15924] ("Information and documentation -- Codes for the representation of names of scripts"), or subsequently assigned by the ISO 15924 registration authority or governing standardization bodies. Only codes assigned by ISO 15924 will be considered for registration.

2. 脚本子标签由四个字母组成,并根据[ISO15924](“信息和文件——脚本名称表示代码”)中的分配进行定义,或随后由ISO 15924注册机构或管理标准化机构进行分配。只有ISO 15924指定的代码才会考虑注册。

3. The script subtags 'Qaaa' through 'Qabx' are reserved for private use in language tags. These subtags correspond to codes reserved by ISO 15924 for private use. These codes MAY be used for non-registered script values. Please refer to Section 4.6 for more information on private use subtags.

3. 脚本子标记“Qaaa”到“Qabx”在语言标记中保留供私人使用。这些子标签对应于ISO 15924保留供私人使用的代码。这些代码可用于未注册的脚本值。有关专用子标签的更多信息,请参阅第4.6节。

4. There MUST be at most one script subtag in a language tag, and the script subtag SHOULD be omitted when it adds no distinguishing value to the tag or when the primary or extended language subtag's record in the subtag registry includes a 'Suppress-Script' field listing the applicable script subtag.

4. 一个语言标记中最多必须有一个脚本子标记,如果脚本子标记未向标记添加任何区分值,或者子标记注册表中的主或扩展语言子标记的记录包含列出适用脚本子标记的“抑制脚本”字段,则应省略该脚本子标记。

For example: "sr-Latn" represents Serbian written using the Latin script.

例如:“sr Latn”代表使用拉丁语书写的塞尔维亚语。

2.2.4. Region Subtag
2.2.4. 区域子标签

Region subtags are used to indicate linguistic variations associated with or appropriate to a specific country, territory, or region. Typically, a region subtag is used to indicate variations such as regional dialects or usage, or region-specific spelling conventions. It can also be used to indicate that content is expressed in a way that is appropriate for use throughout a region, for instance, Spanish content tailored to be useful throughout Latin America.


The following rules apply to the region subtags:


1. Region subtags MUST follow any primary language, extended language, or script subtags and MUST precede any other type of subtag.

1. 区域子标记必须位于任何主语言、扩展语言或脚本子标记之后,并且必须位于任何其他类型的子标记之前。

2. Two-letter region subtags were defined according to the assignments found in [ISO3166-1] ("Codes for the representation of names of countries and their subdivisions -- Part 1: Country codes"), using the list of alpha-2 country codes or using assignments subsequently made by the ISO 3166-1 maintenance agency or governing standardization bodies. In addition, the codes that are "exceptionally reserved" (as opposed to "assigned") in ISO 3166-1 were also defined in the registry, with the exception of 'UK', which is an exact synonym for the assigned code 'GB'.

2. 根据[ISO3166-1](“国家及其子区名称表示代码——第1部分:国家代码”)中的分配,使用alpha-2国家代码列表或ISO 3166-1维护机构或管理标准化机构随后进行的分配,定义了两个字母区域子标签。此外,ISO 3166-1中“例外保留”(相对于“分配”)的代码也在注册中心进行了定义,但“UK”除外,UK是分配代码“GB”的同义词。

3. The region subtags 'AA', 'QM'-'QZ', 'XA'-'XZ', and 'ZZ' are reserved for private use in language tags. These subtags correspond to codes reserved by ISO 3166 for private use. These codes MAY be used for private use region subtags (instead of using a private use subtag sequence). Please refer to Section 4.6 for more information on private use subtags.

3. 区域子标签'AA'、'QM'-'QZ'、'XA'-'XZ'和'ZZ'在语言标签中保留供私人使用。这些子标签对应于ISO 3166保留供私人使用的代码。这些代码可用于专用区域子标记(而不是使用专用子标记序列)。有关专用子标签的更多信息,请参阅第4.6节。

4. Three-character region subtags consist solely of digit (number) characters and were defined according to the assignments found in the UN Standard Country or Area Codes for Statistical Use [UN_M.49] or assignments subsequently made by the governing standards body. Not all of the UN M.49 codes are defined in the IANA registry. The following rules define which codes are entered into the registry as valid subtags:

4. 三字符区域子标签仅由数字(数字)字符组成,并根据联合国统计用标准国家或地区代码[UN_M.49]中的分配或管理标准机构随后进行的分配进行定义。并非所有UN M.49代码都在IANA注册表中定义。以下规则定义哪些代码作为有效子标记输入注册表:

A. UN numeric codes assigned to 'macro-geographical (continental)' or sub-regions MUST be registered in the registry. These codes are not associated with an assigned ISO 3166-1 alpha-2 code and represent supra-national areas, usually covering more than one nation, state, province, or territory.

A.分配给“宏观地理(大陆)”或子区域的非数字代码必须在注册表中注册。这些代码与指定的ISO 3166-1 alpha-2代码无关,代表超国家区域,通常覆盖多个国家、州、省或地区。

B. UN numeric codes for 'economic groupings' or 'other groupings' MUST NOT be registered in the IANA registry and MUST NOT be used to form language tags.


C. When ISO 3166-1 reassigns a code formerly used for one country or area to another country or area and that code already is present in the registry, the UN numeric code for that country or area MUST be registered in the registry as described in Section 3.4 and MUST be used to form language tags that represent the country or region for which it is defined (rather than the recycled ISO 3166-1 code).

C.当ISO 3166-1将以前用于一个国家或地区的代码重新分配给另一个国家或地区,并且该代码已经存在于注册中心时,该国家或地区的联合国数字代码必须按照第3.4节所述在注册表中注册,并且必须用于形成代表其定义国家或地区的语言标签(而不是回收的ISO 3166-1代码)。

D. UN numeric codes for countries or areas for which there is an associated ISO 3166-1 alpha-2 code in the registry MUST NOT be entered into the registry and MUST NOT be used to form language tags. Note that the ISO 3166-based subtag in the registry MUST actually be associated with the UN M.49 code in question.

D.注册表中存在相关ISO 3166-1 alpha-2代码的国家或地区的联合国数字代码不得输入注册表,也不得用于形成语言标签。请注意,注册表中基于ISO 3166的子标记实际上必须与所讨论的UN M.49代码相关联。

E. For historical reasons, the UN numeric code 830 (Channel Islands), which was not registered at the time this document was adopted and had, at that time, no corresponding ISO 3166-1 code, MAY be entered into the IANA registry via the process described in Section 3.5, provided no ISO 3166-1 code with that exact meaning has been previously registered.

E.出于历史原因,联合国数字代码830(海峡岛屿)在采用本文件时未注册,且当时没有相应的ISO 3166-1代码,可通过第3.5节所述的程序输入IANA注册,前提是之前未注册具有确切含义的ISO 3166-1代码。

F. All other UN numeric codes for countries or areas that do not have an associated ISO 3166-1 alpha-2 code MUST NOT be entered into the registry and MUST NOT be used to form language tags. For more information about these codes, see Section 3.4.

F.不具有相关ISO 3166-1 alpha-2代码的国家或地区的所有其他联合国数字代码不得输入注册表,也不得用于形成语言标签。有关这些代码的更多信息,请参见第3.4节。

5. The alphanumeric codes in Appendix X of the UN document MUST NOT be entered into the registry and MUST NOT be used to form language tags. (At the time this document was created, these values matched the ISO 3166-1 alpha-2 codes.)

5. 联合国文件附录X中的字母数字代码不得输入注册表,也不得用于形成语言标签。(创建本文档时,这些值与ISO 3166-1 alpha-2代码匹配。)

6. There MUST be at most one region subtag in a language tag and the region subtag MAY be omitted, as when it adds no distinguishing value to the tag.

6. 语言标记中最多必须有一个region子标记,并且region子标记可以省略,因为它不会向标记添加任何区分值。

For example:


"de-AT" represents German ('de') as used in Austria ('AT').

“de AT”代表在奥地利(“AT”)使用的德语(“de”)。

"sr-Latn-RS" represents Serbian ('sr') written using Latin script ('Latn') as used in Serbia ('RS').

“sr Latn RS”表示塞尔维亚语(“sr”),使用塞尔维亚语(“RS”)中使用的拉丁语(“Latn”)书写。

"es-419" represents Spanish ('es') appropriate to the UN-defined Latin America and Caribbean region ('419').


2.2.5. Variant Subtags
2.2.5. 变异子标签

Variant subtags are used to indicate additional, well-recognized variations that define a language or its dialects that are not covered by other available subtags. The following rules apply to the variant subtags:


1. Variant subtags MUST follow any primary language, extended language, script, or region subtags and MUST precede any extension or private use subtag sequences.

1. 变体子标记必须位于任何主语言、扩展语言、脚本或区域子标记之后,并且必须位于任何扩展或专用子标记序列之前。

2. Variant subtags, as a collection, are not associated with any particular external standard. The meaning of variant subtags in the registry is defined in the course of the registration process defined in Section 3.5. Note that any particular variant subtag might be associated with some external standard. However, association with a standard is not required for registration.

2. 变量子标签作为一个集合,不与任何特定的外部标准关联。注册表中变量子标签的含义在第3.5节定义的注册过程中定义。请注意,任何特定的变体子标记都可能与某些外部标准关联。但是,注册时不需要与标准关联。

3. More than one variant MAY be used to form the language tag.

3. 可以使用多个变体来形成语言标记。

4. Variant subtags MUST be registered with IANA according to the rules in Section 3.5 of this document before being used to form language tags. In order to distinguish variants from other types of subtags, registrations MUST meet the following length and content restrictions:

4. 变体子标签必须根据本文件第3.5节中的规则在IANA注册,然后才能用于形成语言标签。为了将变体与其他类型的子标签区分开来,注册必须满足以下长度和内容限制:

1. Variant subtags that begin with a letter (a-z, A-Z) MUST be at least five characters long.

1. 以字母(a-z,a-z)开头的变体子标签长度必须至少为五个字符。

2. Variant subtags that begin with a digit (0-9) MUST be at least four characters long.

2. 以数字(0-9)开头的变体子标签长度必须至少为四个字符。

5. The same variant subtag MUST NOT be used more than once within a language tag.

5. 同一变体子标记在语言标记中不得使用多次。

* For example, the tag "de-DE-1901-1901" is not valid.

* 例如,标签“de-de-1901-1901”无效。

Variant subtag records in the Language Subtag Registry MAY include one or more 'Prefix' (Section 3.1.8) fields. Each 'Prefix' indicates a suitable sequence of subtags for forming (with other subtags, as appropriate) a language tag when using the variant.


Most variants that share a prefix are mutually exclusive. For example, the German orthographic variations '1996' and '1901' SHOULD NOT be used in the same tag, as they represent the dates of different spelling reforms. A variant that can meaningfully be used in combination with another variant SHOULD include a 'Prefix' field in its registry record that lists that other variant. For example, if another German variant 'example' were created that made sense to use with '1996', then 'example' should include two 'Prefix' fields: "de" and "de-1996".


For example:


"sl-nedis" represents the Natisone or Nadiza dialect of Slovenian.

“sl nedis”代表斯洛文尼亚的Natisone或Nadiza方言。

"de-CH-1996" represents German as used in Switzerland and as written using the spelling reform beginning in the year 1996 C.E.


2.2.6. Extension Subtags
2.2.6. 扩展子标签

Extensions provide a mechanism for extending language tags for use in various applications. They are intended to identify information that is commonly used in association with languages or language tags but that is not part of language identification. See Section 3.7. The following rules apply to extensions:


1. An extension MUST follow at least a primary language subtag. That is, a language tag cannot begin with an extension. Extensions extend language tags, they do not override or replace them. For example, "a-value" is not a well-formed language tag, while "de-a-value" is. Note that extensions cannot be used in tags that are entirely private use (that is, tags starting with "x-").

1. 扩展必须至少跟在主语言子标记后面。也就是说,语言标记不能以扩展名开头。扩展扩展扩展了语言标记,它们不会覆盖或替换它们。例如,“a-value”不是格式良好的语言标记,而“de-a-value”是。请注意,扩展不能用于完全私有的标记(即以“x-”开头的标记)。

2. Extension subtags are separated from the other subtags defined in this document by a single-character subtag (called a "singleton"). The singleton MUST be one allocated to a registration authority via the mechanism described in Section 3.7 and MUST NOT be the letter 'x', which is reserved for private use subtag sequences.

2. 扩展子标签与本文档中定义的其他子标签通过单个字符子标签(称为“singleton”)分开。单件必须是通过第3.7节所述机制分配给注册机构的单件,不得为字母“x”,该字母保留给私人使用的子标签序列。

3. Each singleton subtag MUST appear at most one time in each tag (other than as a private use subtag). That is, singleton subtags MUST NOT be repeated. For example, the tag "en-a-bbb-a-ccc" is invalid because the subtag 'a' appears twice. Note that the tag "en-a-bbb-x-a-ccc" is valid because the second appearance of the singleton 'a' is in a private use sequence.

3. 每个单例子标记必须在每个标记中最多出现一次(专用子标记除外)。也就是说,单例子标记不能重复。例如,标记“en-a-bbb-a-ccc”无效,因为子标记“a”出现两次。请注意,标记“en-a-bbb-x-a-ccc”是有效的,因为单例“a”的第二次出现是在一个私人使用序列中。

4. Extension subtags MUST meet whatever requirements are set by the document that defines their singleton prefix and whatever requirements are provided by the maintaining authority. Note that there might not be a registry of these subtags and validating processors are not required to validate extensions.

4. 扩展子标签必须满足定义其单例前缀的文档设置的任何要求以及维护机构提供的任何要求。请注意,可能没有这些子标签的注册表,验证扩展不需要验证处理器。

5. Each extension subtag MUST be from two to eight characters long and consist solely of letters or digits, with each subtag separated by a single '-'. Case distinctions are ignored in extensions (as with any language subtag) and normalized subtags of this type are expected to be in lowercase.

5. 每个扩展子标记的长度必须为2到8个字符,并且仅由字母或数字组成,每个子标记之间用单个“-”分隔。扩展中的大小写区别被忽略(与任何语言子标记一样),这种类型的规范化子标记应该是小写的。

6. Each singleton MUST be followed by at least one extension subtag. For example, the tag "tlh-a-b-foo" is invalid because the first singleton 'a' is followed immediately by another singleton 'b'.

6. 每个单例后必须至少有一个扩展子标记。例如,标记“tlh-a-b-foo”无效,因为第一个单例“a”后面紧跟着另一个单例“b”。

7. Extension subtags MUST follow all primary language, extended language, script, region, and variant subtags in a tag and MUST precede any private use subtag sequences.

7. 扩展子标记必须位于标记中所有主语言、扩展语言、脚本、区域和变体子标记之后,并且必须位于任何专用子标记序列之前。

8. All subtags following the singleton and before another singleton are part of the extension. Example: In the tag "fr-a-Latn", the subtag 'Latn' does not represent the script subtag 'Latn' defined in the IANA Language Subtag Registry. Its meaning is defined by the extension 'a'.

8. 单例之后和另一单例之前的所有子标记都是扩展的一部分。示例:在标记“fr-a-Latn”中,子标记“Latn”不表示IANA语言子标记注册表中定义的脚本子标记“Latn”。其含义由扩展名“a”定义。

9. In the event that more than one extension appears in a single tag, the tag SHOULD be canonicalized as described in Section 4.5, by ordering the various extension sequences into case-insensitive ASCII order.

9. 如果单个标记中出现多个扩展,则应按照第4.5节所述,通过将各种扩展序列按不区分大小写的ASCII顺序排序,对标记进行规范化。

For example, if an extension were defined for the singleton 'r' and it defined the subtags shown, then the following tag would be a valid example: "en-Latn-GB-boont-r-extended-sequence-x-private".


2.2.7. Private Use Subtags
2.2.7. 专用子标签

Private use subtags are used to indicate distinctions in language that are important in a given context by private agreement. The following rules apply to private use subtags:


1. Private use subtags are separated from the other subtags defined in this document by the reserved single-character subtag 'x'.

1. 专用子标签通过保留的单字符子标签“x”与本文档中定义的其他子标签分开。

2. Private use subtags MUST conform to the format and content constraints defined in the ABNF for all subtags; that is, they MUST consist solely of letters and digits and not exceed eight characters in length.

2. 私用子标签必须符合ABNF中为所有子标签定义的格式和内容约束;也就是说,它们必须仅由字母和数字组成,长度不得超过8个字符。

3. Private use subtags MUST follow all primary language, extended language, script, region, variant, and extension subtags in the tag. Another way of saying this is that all subtags following the singleton 'x' MUST be considered private use. Example: The subtag 'US' in the tag "en-x-US" is a private use subtag.

3. 专用子标签必须位于标签中所有主语言、扩展语言、脚本、区域、变体和扩展子标签之后。另一种说法是,单例“x”后面的所有子标记都必须被视为专用。示例:标记“en-x-US”中的子标记“US”是一个专用子标记。

4. A tag MAY consist entirely of private use subtags.

4. 标记可以完全由专用子标记组成。

5. No source is defined for private use subtags. Use of private use subtags is by private agreement only.

5. 没有为专用子标记定义源。仅通过私人协议使用私人使用子标签。

6. Private use subtags are NOT RECOMMENDED where alternatives exist or for general interchange. See Section 4.6 for more information on private use subtag choice.

6. 如果存在替代方案或用于一般交换,则不建议使用专用子标签。有关专用子标签选择的更多信息,请参见第4.6节。

For example, suppose a group of scholars is studying some texts in medieval Greek. They might agree to use some collection of private use subtags to identify different styles of writing in the texts. For example, they might use 'el-x-koine' for documents in the "common" style while using 'el-x-attic' for other documents that mimic the Attic style. These subtags would not be recognized by outside processes or systems, but might be useful in categorizing various texts for study by those in the group.


In the registry, there are also subtags derived from codes reserved by ISO 639, ISO 15924, or ISO 3166 for private use. Do not confuse these with private use subtag sequences following the subtag 'x'. See Section 4.6.

在注册表中,也有从ISO 639、ISO 15924或ISO 3166保留供私人使用的代码派生的子标签。不要将其与子标记“x”后的专用子标记序列混淆。见第4.6节。

2.2.8. Grandfathered and Redundant Registrations
2.2.8. 祖传和冗余注册

Prior to RFC 4646, whole language tags were registered according to the rules in RFC 1766 and/or RFC 3066. All of these registered tags remain valid as language tags.

在RFC 4646之前,根据RFC 1766和/或RFC 3066中的规则注册了全语言标记。所有这些注册的标记都作为语言标记保持有效。

Many of these registered tags were made redundant by the advent of either RFC 4646 or this document. A redundant tag is a grandfathered registration whose individual subtags appear with the same semantic meaning in the registry. For example, the tag "zh-Hant" (Traditional Chinese) can now be composed from the subtags 'zh' (Chinese) and 'Hant' (Han script traditional variant). These redundant tags are maintained in the registry as records of type 'redundant', mostly as a matter of historical curiosity.

由于RFC 4646或本文件的出现,这些注册标签中的许多都变得多余。冗余标记是一个祖父注册,其各个子标记在注册表中以相同的语义出现。例如,标签“zh Hant”(繁体中文)现在可以由子标签“zh”(中文)和“Hant”(汉字繁体变体)组成。这些冗余标记作为“冗余”类型的记录保存在注册表中,主要是出于历史好奇心。

The remainder of the previously registered tags are "grandfathered". These tags are classified into two groups: 'regular' and 'irregular'.


Grandfathered tags that (appear to) match the 'langtag' production in Figure 1 are considered 'regular' grandfathered tags. These tags contain one or more subtags that either do not individually appear in the registry or appear but with a different semantic meaning: each tag, in its entirety, represents a language or collection of languages.


Grandfathered tags that do not match the 'langtag' production in the ABNF and would otherwise be invalid are considered 'irregular' grandfathered tags. With the exception of "en-GB-oed", which is a variant of "en-GB", each of them, in its entirety, represents a language.

与ABNF中的“langtag”产品不匹配且无效的祖父标记被视为“不规则”祖父标记。除了“en-GB oed”是“en-GB”的一个变体之外,每一个词都代表一种语言。

Many of the grandfathered tags have been superseded by the subsequent addition of new subtags: each superseded record contains a 'Preferred-Value' field that ought to be used to form language tags representing that value. For example, the tag "art-lojban" is superseded by the primary language subtag 'jbo'.

许多父辈标记已被随后添加的新子标记所取代:每个被取代的记录都包含一个“首选值”字段,该字段应用于形成表示该值的语言标记。例如,标记“art lojban”被主语言子标记“jbo”取代。

2.2.9. Classes of Conformance
2.2.9. 一致性类别

Implementations sometimes need to describe their capabilities with regard to the rules and practices described in this document. Tags can be checked or verified in a number of ways, but two particular classes of tag conformance are formally defined here.


A tag is considered "well-formed" if it conforms to the ABNF (Section 2.1). Language tags may be well-formed in terms of syntax but not valid in terms of content. However, many operations involving language tags work well without knowing anything about the meaning or validity of the subtags.


A tag is considered "valid" if it satisfies these conditions:


o The tag is well-formed.

o 标签的格式很好。

o Either the tag is in the list of grandfathered tags or all of its primary language, extended language, script, region, and variant subtags appear in the IANA Language Subtag Registry as of the particular registry date.

o 该标记位于grandfathered标记列表中,或其所有主要语言、扩展语言、脚本、区域和变体子标记在特定注册日期出现在IANA语言子标记注册中。

o There are no duplicate variant subtags.

o 没有重复的变体子标签。

o There are no duplicate singleton (extension) subtags.

o 没有重复的单例(扩展)子标记。

Note that a tag's validity depends on the date of the registry used to validate the tag. A more recent copy of the registry might contain a subtag that an older version does not.


A tag is considered valid for a given extension (Section 3.7) (as of a particular version, revision, and date) if it meets the criteria for "valid" above and also satisfies this condition:


Each subtag used in the extension part of the tag is valid according to the extension.


Older specifications or language tag implementations sometimes reference [RFC3066]. A wider array of tags was considered well-formed under that document. Any tags that were valid for use under RFC 3066 are both well-formed and valid under this document's syntax; only invalid or illegal tags were well-formed under the earlier definition but no longer are. The language tag syntax under RFC 3066 was:

旧的规范或语言标记实现有时引用[RFC3066]。根据该文件,更广泛的标签被认为是格式良好的。在RFC 3066下有效使用的任何标记都是格式良好且在本文档语法下有效的;根据早期的定义,只有无效或非法的标签格式正确,但不再有效。RFC 3066下的语言标记语法为:

       obs-language-tag = primary-subtag *( "-" subtag )
       primary-subtag   = 1*8ALPHA
       subtag           = 1*8(ALPHA / DIGIT)
       obs-language-tag = primary-subtag *( "-" subtag )
       primary-subtag   = 1*8ALPHA
       subtag           = 1*8(ALPHA / DIGIT)

Figure 2: RFC 3066 Language Tag Syntax


Subtags designated for private use as well as private use sequences introduced by the 'x' subtag are available for cases in which no assigned subtags are available and registration is not a suitable option. For example, one might use a tag such as "no-QQ", where 'QQ' is one of a range of private use ISO 3166-1 codes to indicate an otherwise undefined region. Users MUST NOT assign language tags that use subtags that do not appear in the registry other than in private use sequences (such as the subtag 'personal' in the tag "en-x-personal"). Besides not being valid, the user also risks collision with a future possible assignment or registrations.

指定用于私人使用的子标签以及“x”子标签引入的私人使用序列可用于没有指定子标签且注册不是合适选项的情况。例如,可以使用诸如“no QQ”之类的标记,其中“QQ”是一系列私人使用ISO 3166-1代码中的一个,以指示其他未定义的区域。用户不得分配使用子标记的语言标记,这些子标记不出现在注册表中,但在私用序列中除外(例如标记“en-x-personal”中的子标记“personal”)。除了无效外,用户还可能与未来可能的分配或注册发生冲突。

Note well: although the 'Language-Tag' production appearing in this document is functionally equivalent to the one in [RFC4646], it has


been changed to prevent certain errors in well-formedness arising from the old 'grandfathered' production.


3. Registry Format and Maintenance
3. 注册表格式和维护

The IANA Language Subtag Registry ("the registry") contains a comprehensive list of all of the subtags valid in language tags. This allows implementers a straightforward and reliable way to validate language tags. The registry will be maintained so that, except for extension subtags, it is possible to validate all of the subtags that appear in a language tag under the provisions of this document or its revisions or successors. In addition, the meaning of the various subtags will be unambiguous and stable over time. (The meaning of private use subtags, of course, is not defined by the registry.)


This section defines the registry along with the maintenance and update procedures associated with it, as well as a registry for extensions to language tags (Section 3.7).


3.1. Format of the IANA Language Subtag Registry
3.1. IANA语言子标签注册表的格式

The IANA Language Subtag Registry is a machine-readable file in the format described in this section, plus copies of the registration forms approved in accordance with the process described in Section 3.5.


The existing registration forms for grandfathered and redundant tags taken from RFC 3066 have been maintained as part of the obsolete RFC 3066 registry. The subtags added to the registry by either [RFC4645] or [RFC5645] do not have separate registration forms (so no forms are archived for these additions).

从RFC 3066中获取的grandfathered和冗余标签的现有登记表已作为过时RFC 3066注册表的一部分进行了维护。[RFC4645]或[RFC5645]添加到注册表中的子标签没有单独的注册表格(因此这些添加没有存档表格)。

3.1.1. File Format
3.1.1. 文件格式

The registry is a [Unicode] text file and consists of a series of records in a format based on "record-jar" (described in [record-jar]). Each record, in turn, consists of a series of fields that describe the various subtags and tags. The actual registry file is encoded using the UTF-8 [RFC3629] character encoding.

注册表是一个[Unicode]文本文件,由一系列基于“record jar”(在[record jar]中描述)格式的记录组成。每个记录依次由一系列字段组成,这些字段描述各种子标记和标记。实际注册表文件使用UTF-8[RFC3629]字符编码。

Each field can be considered a single, logical line of characters. Each field contains a "field-name" and a "field-body". These are separated by a "field-separator". The field-separator is a COLON character (U+003A) plus any surrounding whitespace. Each field is terminated by the newline sequence CRLF. The text in each field MUST be in Unicode Normalization Form C (NFC).


A collection of fields forms a "record". Records are separated by lines containing only the sequence "%%" (U+0025 U+0025).


Although fields are logically a single line of text, each line of text in the file format is limited to 72 bytes in length. To accommodate this, the field-body can be split into a multiple-line representation; this is called "folding". Folding is done according to customary conventions for line-wrapping. This is typically on whitespace boundaries, but can occur between other characters when the value does not include spaces, such as when a language does not use whitespace between words. In any event, there MUST NOT be breaks inside a multibyte UTF-8 sequence or in the middle of a combining character sequence. For more information, see [UAX14].


Although the file format uses the Unicode character set and the file itself is encoded using the UTF-8 encoding, fields are restricted to the printable characters from the US-ASCII [ISO646] repertoire unless otherwise indicated in the description of a specific field (Section 3.1.2).


The format of the registry is described by the following ABNF [RFC5234]. Character numbers (code points) are taken from Unicode, and terminals in the ABNF productions are in terms of characters rather than bytes.


   registry   = record *("%%" CRLF record)
   record     = 1*field
   field      = ( field-name field-sep field-body CRLF )
   field-name = (ALPHA / DIGIT) [*(ALPHA / DIGIT / "-") (ALPHA / DIGIT)]
   field-sep  = *SP ":" *SP
   field-body = *([[*SP CRLF] 1*SP] 1*CHARS)
   CHARS      = (%x21-10FFFF)      ; Unicode code points
   registry   = record *("%%" CRLF record)
   record     = 1*field
   field      = ( field-name field-sep field-body CRLF )
   field-name = (ALPHA / DIGIT) [*(ALPHA / DIGIT / "-") (ALPHA / DIGIT)]
   field-sep  = *SP ":" *SP
   field-body = *([[*SP CRLF] 1*SP] 1*CHARS)
   CHARS      = (%x21-10FFFF)      ; Unicode code points

Figure 3: Registry Format ABNF


The sequence '..' (U+002E U+002E) in a field-body denotes a range of values. Such a range represents all subtags of the same length that are in alphabetic or numeric order within that range, including the values explicitly mentioned. For example, 'a..c' denotes the values 'a', 'b', and 'c', and '11..13' denotes the values '11', '12', and '13'.

字段正文中的序列“..”(U+002E U+002E)表示值的范围。该范围表示该范围内以字母或数字顺序排列的相同长度的所有子标签,包括明确提到的值。例如,“a..c”表示值“a”、“b”和“c”,“11..13”表示值“11”、“12”和“13”。

All fields whose field-body contains a date value use the "full-date" format specified in [RFC3339]. For example, "2004-06-28" represents June 28, 2004, in the Gregorian calendar.


3.1.2. Record and Field Definitions
3.1.2. 记录和字段定义

There are three types of records in the registry: "File-Date", "Subtag", and "Tag".


The first record in the registry is always the "File-Date" record. This record occurs only once in the file and contains a single field whose field-name is "File-Date". The field-body of this record contains a date (see Section 5.1), making it possible to easily recognize different versions of the registry.


File-Date: 2004-06-28 %%


Figure 4: Example of the File-Date Record


Subsequent records contain multiple fields and represent information about either subtags or tags. Both types of records have an identical structure, except that "Subtag" records contain a field with a field-name of "Subtag", while, unsurprisingly, "Tag" records contain a field with a field-name of "Tag". Field-names MUST NOT occur more than once per record, with the exception of the 'Description', 'Comments', and 'Prefix' fields.


Each record MUST contain at least one of each of the following fields:


o 'Type'

o “类型”

* Type's field-body MUST consist of one of the following strings: "language", "extlang", "script", "region", "variant", "grandfathered", and "redundant"; it denotes the type of tag or subtag.

* 类型的字段体必须由以下字符串之一组成:“语言”、“extlang”、“脚本”、“区域”、“变体”、“祖父”和“冗余”;它表示标记或子标记的类型。

o Either 'Subtag' or 'Tag'

o “子标签”或“标签”

* Subtag's field-body contains the subtag being defined. This field MUST appear in all records whose 'Type' has one of these values: "language", "extlang", "script", "region", or "variant".

* 子标记的字段体包含正在定义的子标记。此字段必须出现在“类型”具有以下值之一的所有记录中:“语言”、“extlang”、“脚本”、“区域”或“变体”。

* Tag's field-body contains a complete language tag. This field MUST appear in all records whose 'Type' has one of these values: "grandfathered" or "redundant". If the 'Type' is "grandfathered", then the 'Tag' field-body will be one of the tags listed in either the 'regular' or 'irregular' production found in Section 2.1.

* 标记的字段体包含完整的语言标记。此字段必须出现在“Type”具有以下值之一的所有记录中:“grandfathered”或“redundant”。如果“类型”为“grandfathered”,则“标记”字段主体将是第2.1节中“常规”或“非常规”生产中列出的标记之一。

o 'Description'

o “说明”

* Description's field-body contains a non-normative description of the subtag or tag.

* 描述的字段体包含子标记或标记的非规范性描述。

o 'Added'

o ‘补充’

* Added's field-body contains the date the record was registered or, in the case of grandfathered or redundant tags, the date the corresponding tag was registered under the rules of [RFC1766] or [RFC3066].

* Added的字段体包含记录的注册日期,或者,如果是grandfathered或冗余标记,则包含根据[RFC1766]或[RFC3066]规则注册相应标记的日期。

Each record MAY also contain the following fields:


o 'Deprecated'

o “弃用”

* Deprecated's field-body contains the date the record was deprecated. In some cases, this value is earlier than that of the 'Added' field in the same record. That is, the date of deprecation preceded the addition of the record to the registry.

* 弃用的字段正文包含记录弃用的日期。在某些情况下,此值早于同一记录中“已添加”字段的值。也就是说,弃用日期在将记录添加到注册表之前。

o 'Preferred-Value'

o “首选值”

* Preferred-Value's field-body contains a canonical mapping from this record's value to a modern equivalent that is preferred in its place. Depending on the value of the 'Type' field, this value can take different forms:

* Preferred Value的字段体包含从该记录的值到首选的现代等效值的规范映射。根据“类型”字段的值,此值可以采用不同的形式:

+ For fields of type 'language', 'Preferred-Value' contains the primary language subtag that is preferred when forming the language tag.

+ 对于“语言”类型的字段,“首选值”包含形成语言标记时首选的主语言子标记。

+ For fields of type 'script', 'region', or 'variant', 'Preferred-Value' contains the subtag of the same type that is preferred for forming the language tag.

+ 对于“script”、“region”或“variant”类型的字段,“Preferred Value”包含构成语言标记首选的相同类型的子标记。

+ For fields of type 'extlang', 'grandfathered', or 'redundant', 'Preferred-Value' contains an "extended language range" [RFC4647] that is preferred for forming the language tag. That is, the preferred language tag will contain, in order, each of the subtags that appears in the 'Preferred-Value'; additional fields can be included in a language tag, as described elsewhere in this document. For example, the replacement for the grandfathered tag "zh-min-nan" (Min Nan Chinese) is "nan", which can be used as the

+ 对于“extlang”、“grandfathered”或“redundant”类型的字段,“Preferred Value”包含一个“extended language range”[RFC4647],它是构成语言标记的首选字段。也就是说,首选语言标记将依次包含“首选值”中出现的每个子标记;如本文档其他部分所述,语言标记中可以包含其他字段。例如,祖辈标记“zh min nan”(min nan中文)的替换词是“nan”,可以用作

basis for tags such as "nan-Hant" or "nan-TW" (note that the extended language subtag form such as "zh-nan-Hant" or "zh-nan-TW" can also be used).


o 'Prefix'

o “前缀”

* Prefix's field-body contains a valid language tag that is RECOMMENDED as one possible prefix to this record's subtag. This field MAY appear in records whose 'Type' field-body is either 'extlang' or 'variant' (it MUST NOT appear in any other record type).

* Prefix的字段体包含一个有效的语言标记,建议将其作为此记录的子标记的一个可能前缀。此字段可能出现在“Type”字段主体为“extlang”或“variant”的记录中(不得出现在任何其他记录类型中)。

o 'Suppress-Script'

o “抑制脚本”

* Suppress-Script's field-body contains a script subtag that SHOULD NOT be used to form language tags with the associated primary or extended language subtag. This field MUST appear only in records whose 'Type' field-body is 'language' or 'extlang'. See Section 4.1.

* 抑制脚本的字段体包含一个脚本子标记,该脚本子标记不应用于与关联的主或扩展语言子标记形成语言标记。此字段只能出现在“类型”字段主体为“语言”或“extlang”的记录中。见第4.1节。

o 'Macrolanguage'

o “宏语言”

* Macrolanguage's field-body contains a primary language subtag defined by ISO 639 as the "macrolanguage" that encompasses this language subtag. This field MUST appear only in records whose 'Type' field-body is either 'language' or 'extlang'.

* 宏语言的字段体包含一个由ISO 639定义为“宏语言”的主语言子标记,该“宏语言”包含该语言子标记。此字段必须仅出现在“Type”字段体为“language”或“extlang”的记录中。

o 'Scope'

o “范围”

* Scope's field-body contains information about a primary or extended language subtag indicating the type of language code according to ISO 639. The values permitted in this field are "macrolanguage", "collection", "special", and "private-use". This field only appears in records whose 'Type' field-body is either 'language' or 'extlang'. When this field is omitted, the language is an individual language.

* 范围的字段体包含有关主语言或扩展语言子标记的信息,根据ISO 639指示语言代码的类型。此字段中允许的值为“宏语言”、“集合”、“特殊”和“私人使用”。此字段仅出现在“Type”字段体为“language”或“extlang”的记录中。如果省略此字段,则该语言为单独的语言。

o 'Comments'

o “评论”

* Comments's field-body contains additional information about the subtag, as deemed appropriate for understanding the registry and implementing language tags using the subtag or tag.

* Comments的字段体包含关于子标记的附加信息,这对于理解注册表和使用子标记或标记实现语言标记是合适的。

Future versions of this document might add additional fields to the registry; implementations SHOULD ignore fields found in the registry that are not defined in this document.


3.1.3. Type Field
3.1.3. 类型字段

The field 'Type' contains the string identifying the record type in which it appears. Values for the 'Type' field-body are: "language" (Section 2.2.1); "extlang" (Section 2.2.2); "script" (Section 2.2.3); "region" (Section 2.2.4); "variant" (Section 2.2.5); "grandfathered" or "redundant" (Section 2.2.8).


3.1.4. Subtag and Tag Fields
3.1.4. 子标记和标记字段

The field 'Subtag' contains the subtag defined in the record. The field 'Tag' appears in records whose 'Type' is either 'grandfathered' or 'redundant' and contains a tag registered under [RFC3066].


The 'Subtag' field-body MUST follow the casing conventions described in Section 2.1.1. All subtags use lowercase letters in the field-body, with two exceptions:


Subtags whose 'Type' field is 'script' (in other words, subtags defined by ISO 15924) MUST use titlecase.

“Type”字段为“script”的子标签(换句话说,ISO 15924定义的子标签)必须使用titlecase。

Subtags whose 'Type' field is 'region' (in other words, the non-numeric region subtags defined by ISO 3166-1) MUST use all uppercase.

“类型”字段为“区域”的子标记(换句话说,ISO 3166-1定义的非数字区域子标记)必须使用所有大写字母。

The 'Tag' field-body MUST be formatted according to the rules described in Section 2.1.1.


3.1.5. Description Field
3.1.5. 描述字段

The field 'Description' contains a description of the tag or subtag in the record. The 'Description' field MAY appear more than once per record. The 'Description' field MAY include the full range of Unicode characters. At least one of the 'Description' fields MUST be written or transcribed into the Latin script; additional 'Description' fields MAY be in any script or language.


The 'Description' field is used for identification purposes. Descriptions SHOULD contain all and only that information necessary to distinguish one subtag from others with which it might be confused. They are not intended to provide general background information or to provide all possible alternate names or designations. 'Description' fields don't necessarily represent the actual native name of the item in the record, nor are any of the descriptions guaranteed to be in any particular language (such as English or French, for example).


Descriptions in the registry that correspond to ISO 639, ISO 15924, ISO 3166-1, or UN M.49 codes are intended only to indicate the meaning of that identifier as defined in the source standard at the time it was added to the registry or as subsequently modified, within the bounds of the stability rules (Section 3.4), via subsequent registration. The 'Description' does not replace the content of the source standard itself. 'Description' fields are not intended to be the localized English names for the subtags. Localization or translation of language tag and subtag descriptions is out of scope of this document.

注册中心中与ISO 639、ISO 15924、ISO 3166-1或UN M.49代码相对应的描述仅用于指示源标准中定义的标识符的含义,该标识符在添加到注册中心时定义,或在稳定性规则(第3.4节)的范围内通过后续注册进行后续修改。“说明”并不取代源标准本身的内容。”“说明”字段不是子标签的本地化英文名称。语言标记和子标记描述的本地化或翻译不在本文档范围内。

For subtags taken from a source standard (such as ISO 639 or ISO 15924), the 'Description' fields in the record are also initially taken from that source standard. Multiple descriptions in the source standard are split into separate 'Description' fields. The source standard's descriptions MAY be edited or modified, either prior to insertion or via the registration process, and additional or extraneous descriptions omitted or removed. Each 'Description' field MUST be unique within the record in which it appears, and formatting variations of the same description SHOULD NOT occur in that specific record. For example, while the ISO 639-1 code 'fy' has both the description "Western Frisian" and the description "Frisian, Western" in that standard, only one of these descriptions appears in the registry.

对于源标准(如ISO 639或ISO 15924)中的子标记,记录中的“描述”字段最初也取自该源标准。源标准中的多个描述被拆分为单独的“描述”字段。可在插入之前或通过注册过程编辑或修改源标准的说明,并省略或删除额外或无关的说明。每个“描述”字段在其出现的记录中必须是唯一的,并且该特定记录中不应出现相同描述的格式变化。例如,虽然ISO 639-1代码“fy”在该标准中既有“西弗里斯兰”的描述,也有“西弗里斯兰”的描述,但这些描述中只有一个出现在注册表中。

To help ensure that users do not become confused about which subtag to use, 'Description' fields assigned to a record of any specific type ('language', 'extlang', 'script', and so on) MUST be unique within that given record type with the following exception: if a particular 'Description' field occurs in multiple records of a given type, then at most one of the records can omit the 'Deprecated' field. All deprecated records that share a 'Description' MUST have the same 'Preferred-Value', and all non-deprecated records MUST be that 'Preferred-Value'. This means that two records of the same type that share a 'Description' are also semantically equivalent and no more than one record with a given 'Description' is preferred for that meaning.


For example, consider the 'language' subtags 'zza' (Zaza) and 'diq' (Dimli). It so happens that 'zza' is a macrolanguage enclosing 'diq' and thus also has a description in ISO 639-3 of "Dimli". This description was edited to read "Dimli (macrolanguage)" in the registry record for 'zza' to prevent a collision.

例如,考虑“语言”子标记“ZZA”(ZAZA)和“DIQ”(DIMLI)。碰巧“zza”是一种包含“diq”的宏语言,因此在ISO 639-3中也有“Dimli”的描述。此说明已编辑为“zza”注册表记录中的“Dimli(宏语言)”,以防止冲突。

By contrast, the subtags 'he' and 'iw' share a 'Description' value of "Hebrew"; this is permitted because 'iw' is deprecated and its 'Preferred-Value' is 'he'.


For fields of type 'language', the first 'Description' field appearing in the registry corresponds whenever possible to the Reference Name assigned by ISO 639-3. This helps facilitate cross-referencing between ISO 639 and the registry.

对于“语言”类型的字段,注册表中出现的第一个“描述”字段尽可能与ISO 639-3指定的参考名称相对应。这有助于促进ISO 639和注册中心之间的交叉引用。

When creating or updating a record due to the action of one of the source standards, the Language Subtag Reviewer MAY edit descriptions to correct irregularities in formatting (such as misspellings, inappropriate apostrophes or other punctuation, or excessive or missing spaces) prior to submitting the proposed record to the list for consideration.


3.1.6. Deprecated Field
3.1.6. 弃用字段

The field 'Deprecated' contains the date the record was deprecated and MAY be added, changed, or removed from any record via the maintenance process described in Section 3.3 or via the registration process described in Section 3.5. Usually, the addition of a 'Deprecated' field is due to the action of one of the standards bodies, such as ISO 3166, withdrawing a code. Although valid in language tags, subtags and tags with a 'Deprecated' field are deprecated, and validating processors SHOULD NOT generate these subtags. Note that a record that contains a 'Deprecated' field and no corresponding 'Preferred-Value' field has no replacement mapping.

字段“弃用”包含记录弃用的日期,可通过第3.3节所述的维护过程或第3.5节所述的注册过程从任何记录中添加、更改或删除。通常,添加“弃用”字段是由于某个标准机构(如ISO 3166)撤消代码的行为。虽然在语言标记中有效,但子标记和带有“Deprecated”字段的标记已被弃用,验证处理器不应生成这些子标记。请注意,包含“已弃用”字段且没有相应“首选值”字段的记录没有替换映射。

In some historical cases, it might not have been possible to reconstruct the original deprecation date. For these cases, an approximate date appears in the registry. Some subtags and some grandfathered or redundant tags were deprecated before the initial creation of the registry. The exact rules for this appear in Section 2 of [RFC4645]. Note that these records have a 'Deprecated' field with an earlier date then the corresponding 'Added' field!


3.1.7. Preferred-Value Field
3.1.7. 首选值字段

The field 'Preferred-Value' contains a mapping between the record in which it appears and another tag or subtag (depending on the record's 'Type'). The value in this field is used for canonicalization (see Section 4.5). In cases where the subtag or tag also has a 'Deprecated' field, then the 'Preferred-Value' is RECOMMENDED as the best choice to represent the value of this record when selecting a language tag.


Records containing a 'Preferred-Value' fall into one of these four groups:


1. ISO 639 language codes that were later withdrawn in favor of other codes. These values are mostly a historical curiosity. The 'he'/'iw' pairing above is an example of this.

1. ISO 639语言代码,后来被撤销,取而代之的是其他代码。这些价值观大多是一种历史好奇心。上面的‘he’/‘iw’配对就是一个例子。

2. Subtags (with types other than language or extlang) taken from codes or values that have been withdrawn in favor of a new code. In particular, this applies to region subtags taken from ISO 3166-1, because sometimes a country will change its name or administration in such a way that warrants a new region code. In some cases, countries have reverted to an older name, which might already be encoded. For example, the subtag 'ZR' (Zaire) was replaced by the subtag 'CD' (Democratic Republic of the Congo) when that country's name was changed.

2. 子标记(具有除language或extlang以外的类型)取自代码或值,这些代码或值已被撤回以支持新代码。特别是,这适用于ISO 3166-1中的地区子标签,因为有时一个国家会以需要新地区代码的方式更改其名称或管理。在某些情况下,国家已恢复为旧名称,该名称可能已经编码。例如,当刚果民主共和国的名称发生变化时,“ZR”(扎伊尔)子标签被“CD”(刚果民主共和国)子标签所取代。

3. Tags or subtags that have become obsolete because the values they represent were later encoded. Many of the grandfathered or redundant tags were later encoded by ISO 639, for example, and fall into this grouping. For example, "i-klingon" was deprecated when the subtag 'tlh' was added. The record for "i-klingon" has a 'Preferred-Value' of 'tlh'.

3. 已过时的标记或子标记,因为它们所代表的值后来被编码。例如,许多祖传的或冗余的标签后来被ISO 639编码,并归入这一组。例如,在添加子标签“tlh”时,“i-klingon”被弃用。“i-klingon”记录的“首选值”为“tlh”。

4. Extended language subtags always have a mapping to their identical primary language subtag. For example, the extended language subtag 'yue' (Cantonese) can be used to form the tag "zh-yue". It has a 'Preferred-Value' mapping to the primary language subtag 'yue', meaning that a tag such as "zh-yue-Hant-HK" can be canonicalized to "yue-Hant-HK".

4. 扩展语言子标签始终具有到其相同主语言子标签的映射。例如,扩展语言子标签'yue'(粤语)可用于形成标签“zh yue”。它有一个“首选值”映射到主语言子标签“yue”,这意味着“zh yue Hant HK”等标签可以规范化为“yue Hant HK”。

Records other than those of type 'extlang' that contain a 'Preferred-Value' field MUST also have a 'Deprecated' field. This field contains the date on which the tag or subtag was deprecated in favor of the preferred value.


For records of type 'extlang', the 'Preferred-Value' field appears without a corresponding 'Deprecated' field. An implementation MAY ignore these preferred value mappings, although if it ignores the mapping, it SHOULD do so consistently. It SHOULD also treat the 'Preferred-Value' as equivalent to the mapped item. For example, the tags "zh-yue-Hant-HK" and "yue-Hant-HK" are semantically equivalent and ought to be treated as if they were the same tag.

对于“extlang”类型的记录,“Preferred Value”字段显示时没有相应的“Deprecated”字段。一个实现可能会忽略这些首选值映射,尽管如果它忽略了映射,它应该始终如一地这样做。它还应将“首选值”视为等同于映射项。例如,标记“zh yue Hant HK”和“yue Hant HK”在语义上是等价的,应该将它们视为相同的标记。

Occasionally, the deprecated code is preferred in certain contexts. For example, both "iw" and "he" can be used in the Java programming language, but "he" is converted on input to "iw", which is thus the canonical form in Java.


'Preferred-Value' mappings in records of type 'region' sometimes do not represent exactly the same meaning as the original value. There are many reasons for a country code to be changed, and the effect this has on the formation of language tags will depend on the nature of the change in question. For example, the region subtag 'YD' (Democratic Yemen) was deprecated in favor of the subtag 'YE' (Yemen) when those two countries unified in 1990.

“region”类型记录中的“Preferred Value”映射有时表示的含义与原始值不完全相同。更改国家代码有很多原因,而这对语言标记形成的影响将取决于相关更改的性质。例如,1990年两国统一时,该地区的“YD”(民主也门)子区被弃用,取而代之的是“YE”(也门)子区。

A 'Preferred-Value' MAY be added to, changed, or removed from records according to the rules in Section 3.3. Addition, modification, or removal of a 'Preferred-Value' field in a record does not imply that content using the affected subtag needs to be retagged.


The 'Preferred-Value' fields in records of type "grandfathered" and "redundant" each contain an "extended language range" [RFC4647] that is strongly RECOMMENDED for use in place of the record's value. In many cases, these mappings were created via deprecation of the tags during the period before [RFC4646] was adopted. For example, the tag "no-nyn" was deprecated in favor of the ISO 639-1-defined language code 'nn'.

“grandfathered”和“redundant”类型记录中的“Preferred Value”字段均包含一个“extended language range”[RFC4647],强烈建议使用该字段代替记录的值。在许多情况下,这些映射是在[RFC4646]被采用之前通过弃用标记创建的。例如,标签“no-nyn”被弃用,取而代之的是ISO 639-1定义的语言代码“nn”。

The 'Preferred-Value' field in subtag records of type "extlang" also contains an "extended language range". This allows the subtag to be deprecated in favor of either a single primary language subtag or a new language-extlang sequence.


Usually, the addition, removal, or change of a 'Preferred-Value' field for a subtag is done to reflect changes in one of the source standards. For example, if an ISO 3166-1 region code is deprecated in favor of another code, that SHOULD result in the addition of a 'Preferred-Value' field.

通常,添加、删除或更改子标记的“首选值”字段是为了反映源标准之一的更改。例如,如果一个ISO 3166-1地区代码被弃用而代之以另一个代码,则应增加一个“首选值”字段。

Changes to one subtag can affect other subtags as well: when proposing changes to the registry, the Language Subtag Reviewer MUST review the registry for such effects and propose the necessary changes using the process in Section 3.5, although anyone MAY request such changes. For example:


Suppose that subtag 'XX' has a 'Preferred-Value' of 'YY'. If 'YY' later changes to have a 'Preferred-Value' of 'ZZ', then the 'Preferred-Value' for 'XX' MUST also change to be 'ZZ'.


Suppose that a registered language subtag 'dialect' represents a language not yet available in any part of ISO 639. The later addition of a corresponding language code in ISO 639 SHOULD result in the addition of a 'Preferred-Value' for 'dialect'.

假设注册语言子标签“方言”表示ISO 639任何部分中尚未提供的语言。ISO 639中随后添加的相应语言代码应导致为“方言”添加“首选值”。

3.1.8. Prefix Field
3.1.8. 前缀字段

The field 'Prefix' contains a valid language tag that is RECOMMENDED as one possible prefix to this record's subtag, perhaps with other subtags. That is, when including an extended language or a variant subtag that has at least one 'Prefix' in a language tag, the resulting tag SHOULD match at least one of the subtag's 'Prefix' fields using the "Extended Filtering" algorithm (see [RFC4647]), and each of the subtags in that 'Prefix' SHOULD appear before the subtag itself.


The 'Prefix' field MUST appear exactly once in a record of type 'extlang'. The 'Prefix' field MAY appear multiple times (or not at all) in records of type 'variant'. Additional fields of this type MAY be added to a 'variant' record via the registration process, provided the 'variant' record already has at least one 'Prefix' field.


Each 'Prefix' field indicates a particular sequence of subtags that form a meaningful tag with this subtag. For example, the extended language subtag 'cmn' (Mandarin Chinese) only makes sense with its prefix 'zh' (Chinese). Similarly, 'rozaj' (Resian, a dialect of Slovenian) would be appropriate when used with its prefix 'sl' (Slovenian), while tags such as "is-1994" are not appropriate (and probably not meaningful). Although the 'Prefix' for 'rozaj' is "sl", other subtags might appear between them. For example, the tag "sl-IT-rozaj" (Slovenian, Italy, Resian) matches the 'Prefix' "sl".

每个“Prefix”字段表示与此子标记形成有意义标记的特定子标记序列。例如,扩展语言子标签“cmn”(普通话)仅在前缀“zh”(中文)时才有意义。类似地,“rozaj”(Resian,斯洛文尼亚方言)与其前缀“sl”(斯洛文尼亚语)一起使用时将是合适的,而“is-1994”等标记则不合适(并且可能没有意义)。虽然“rozaj”的“前缀”是“sl”,但它们之间可能会出现其他子标签。例如,标记“sl IT rozaj”(斯洛文尼亚语、意大利语、Resian语)与“前缀”匹配。

The 'Prefix' also indicates when variant subtags make sense when used together (many that otherwise share a 'Prefix' are mutually exclusive) and what the relative ordering of variants is supposed to be. For example, the variant '1994' (Standardized Resian orthography) has several 'Prefix' fields in the registry ("sl-rozaj", "sl-rozaj-biske", "sl-rozaj-njiva", "sl-rozaj-osojs", and "sl-rozaj-solba"). This indicates not only that '1994' is appropriate to use with each of these five Resian variant subtags ('rozaj', 'biske', 'njiva', 'osojs', and 'solba'), but also that it SHOULD appear following any of these variants in a tag. Thus, the language tag ought to take the form "sl-rozaj-biske-1994", rather than "sl-1994- rozaj-biske" or "sl-rozaj-1994-biske".

“前缀”还表示变量子标记在一起使用时的意义(许多共享“前缀”的子标记是互斥的)以及变量的相对顺序。例如,变体“1994”(标准化的Resian拼字法)在注册表中有几个“前缀”字段(“sl rozaj”、“sl rozaj biske”、“sl rozaj njiva”、“sl rozaj osojs”和“sl rozaj solba”)。这不仅表明“1994”适用于这五个Resian变体子标签(“rozaj”、“biske”、“njiva”、“osojs”和“solba”)中的每一个,而且还表明它应该出现在标签中这些变体的后面。因此,语言标签应采用“sl-rozaj-biske-1994”的形式,而不是“sl-1994-rozaj-biske”或“sl-rozaj-1994-biske”。

If a record includes no 'Prefix' field, a 'Prefix' field MUST NOT be added to the record at a later date. Otherwise, changes (additions, deletions, or modifications) to the set of 'Prefix' fields MAY be registered, as long as they strictly widen the range of language tags that are recommended. For example, a 'Prefix' with the value "be-Latn" (Belarusian, Latin script) could be replaced by the value "be" (Belarusian) but not by the value "ru-Latn" (Russian, Latin script)


or the value "be-Latn-BY" (Belarusian, Latin script, Belarus), since these latter either change or narrow the range of suggested tags.

或者值“be Latn BY”(白俄罗斯语,拉丁语,白俄罗斯语),因为后者改变或缩小了建议标记的范围。

The field-body of the 'Prefix' field MUST NOT conflict with any 'Prefix' already registered for a given record. Such a conflict would occur when no valid tag could be constructed that would contain the prefix, such as when two subtags each have a 'Prefix' that contains the other subtag. For example, suppose that the subtag 'avariant' has the prefix "es-bvariant". Then the subtag 'bvariant' cannot be assigned the prefix 'avariant', for that would require a tag of the form "es-avariant-bvariant-avariant", which would not be valid.

“Prefix”字段的字段体不得与已为给定记录注册的任何“Prefix”冲突。当无法构造包含前缀的有效标记时,例如当两个子标记各自具有包含另一个子标记的“前缀”时,就会发生这种冲突。例如,假设子标签“avariant”具有前缀“es BVVariant”。那么子标签“bvariant”不能被分配前缀“avariant”,因为这将需要一个形式为“es avariant bvariant avariant”的标签,这将是无效的。

3.1.9. Suppress-Script Field
3.1.9. 抑制脚本字段

The field 'Suppress-Script' contains a script subtag (whose record appears in the registry). The field 'Suppress-Script' MUST appear only in records whose 'Type' field-body is either 'language' or 'extlang'. This field MUST NOT appear more than one time in a record.

“抑制脚本”字段包含脚本子标记(其记录显示在注册表中)。字段“Suppress Script”只能出现在“Type”字段体为“language”或“extlang”的记录中。此字段在记录中不得出现多次。

This field indicates a script used to write the overwhelming majority of documents for the given language. The subtag for such a script therefore adds no distinguishing information to a language tag and thus SHOULD NOT be used for most documents in that language. Omitting the script subtag indicated by this field helps ensure greater compatibility between the language tags generated according to the rules in this document and language tags and tag processors or consumers based on RFC 3066. For example, virtually all Icelandic documents are written in the Latin script, making the subtag 'Latn' redundant in the tag "is-Latn".

此字段表示用于为给定语言编写绝大多数文档的脚本。因此,此类脚本的子标记不会向语言标记添加任何区别信息,因此不应用于该语言中的大多数文档。省略此字段指示的脚本子标记有助于确保根据本文档中的规则生成的语言标记与基于RFC 3066的语言标记和标记处理者或使用者之间更大的兼容性。例如,几乎所有冰岛文档都是用拉丁语书写的,这使得标记“is Latn”中的子标记“Latn”是多余的。

Many language subtag records do not have a 'Suppress-Script' field. The lack of a 'Suppress-Script' might indicate that the language is customarily written in more than one script or that the language is not customarily written at all. It might also mean that sufficient information was not available when the record was created and thus remains a candidate for future registration.


3.1.10. Macrolanguage Field
3.1.10. 宏语言场

The field 'Macrolanguage' contains a primary language subtag (whose record appears in the registry). This field indicates a language that encompasses this subtag's language according to assignments made by ISO 639-3.

“宏语言”字段包含一个主语言子标记(其记录显示在注册表中)。此字段表示根据ISO 639-3指定的包含此子标签语言的语言。

ISO 639-3 labels some languages in the registry as "macrolanguages". ISO 639-3 defines the term "macrolanguage" to mean "clusters of

ISO 639-3将注册表中的某些语言标记为“宏语言”。ISO 639-3将术语“宏语言”定义为“集群”

closely-related language varieties that [...] can be considered distinct individual languages, yet in certain usage contexts a single language identity for all is needed". These correspond to codes registered in ISO 639-2 as individual languages that were found to correspond to more than one language in ISO 639-3.

密切相关的语言变体,[…]可被视为不同的单独语言,但在某些使用上下文中,需要为所有语言提供一个单一的语言标识”。这些代码对应于ISO 639-2中注册为单独语言的代码,这些代码被发现对应于ISO 639-3中的一种以上语言。

A language contained within a macrolanguage is called an "encompassed language". The record for each encompassed language contains a 'Macrolanguage' field in the registry; the macrolanguages themselves are not specially marked. Note that some encompassed languages have ISO 639-1 or ISO 639-2 codes.

包含在宏语言中的语言称为“包含的语言”。每个包含语言的记录在注册表中包含一个“宏语言”字段;宏语言本身没有特别标记。请注意,一些包含的语言具有ISO 639-1或ISO 639-2代码。

The 'Macrolanguage' field can only occur in records of type 'language' or 'extlang'. Only values assigned by ISO 639-3 will be considered for inclusion. 'Macrolanguage' fields MAY be added or removed via the normal registration process whenever ISO 639-3 defines new values or withdraws old values. Macrolanguages are informational, and MAY be removed or changed if ISO 639-3 changes the values. For more information on the use of this field and choosing between macrolanguage and encompassed language subtags, see Section 4.1.1.

“宏语言”字段只能出现在“语言”或“extlang”类型的记录中。只有ISO 639-3指定的值才会考虑纳入。”每当ISO 639-3定义新值或提取旧值时,可通过正常注册过程添加或删除“宏语言”字段。宏语言是信息性的,如果ISO 639-3更改值,宏语言可能会被删除或更改。有关使用此字段以及在宏语言和包含的语言子标签之间进行选择的更多信息,请参见第4.1.1节。

For example, the language subtags 'nb' (Norwegian Bokmal) and 'nn' (Norwegian Nynorsk) each have a 'Macrolanguage' field with a value of 'no' (Norwegian). For more information, see Section 4.1.


3.1.11. Scope Field
3.1.11. 范围字段

The field 'Scope' contains classification information about a primary or extended language subtag derived from ISO 639. Most languages have a scope of 'individual', which means that the language is not a macrolanguage, collection, special code, or private use. That is, it is what one would normally consider to be 'a language'. Any primary or extended language subtag that has no 'Scope' field is an individual language.

字段“Scope”包含有关源自ISO 639的主语言或扩展语言子标记的分类信息。大多数语言都有“个人”的范围,这意味着该语言不是宏语言、集合、特殊代码或私人用途。也就是说,人们通常认为它是“一种语言”。没有“范围”字段的任何主语言或扩展语言子标记都是单独的语言。

'Scope' information can sometimes be helpful in selecting language tags, since it indicates the purpose or "scope" of the code assignment within ISO 639. The available values are:

“范围”信息有时有助于选择语言标记,因为它指示ISO 639中代码分配的目的或“范围”。可用值为:

o 'macrolanguage' - Indicates a macrolanguage as defined by ISO 639-3 (see Section 3.1.10). A macrolanguage is a cluster of closely related languages that are sometimes considered to be a single language.

o “宏语言”-表示ISO 639-3定义的宏语言(见第3.1.10节)。宏语言是一组密切相关的语言,有时被认为是单一语言。

o 'collection' - Indicates a subtag that represents a collection of languages, typically related by some type of historical, geographical, or linguistic association. Unlike a macrolanguage,

o “集合”-表示表示语言集合的子标记,通常由某种类型的历史、地理或语言关联相关。与宏语言不同,

a collection can contain languages that are only loosely related and a collection cannot be used interchangeably with languages that belong to it.


o 'special' - Indicates a special language code. These are subtags used for identifying linguistic attributes not particularly associated with a concrete language. These include codes for when the language is undetermined or for non-linguistic content.

o “特殊”-表示特殊语言代码。这些子标签用于识别与具体语言无关的语言属性。这些代码包括不确定语言或非语言内容的代码。

o 'private-use' - Indicates a code reserved for private use in the underlying standard. Subtags with this scope can be used to indicate a primary language for which no ISO 639 or registered assignment exists.

o “专用”-表示基础标准中为专用而保留的代码。具有此作用域的子标记可用于指示不存在ISO 639或注册赋值的主语言。

The 'Scope' field MAY appear in records of type 'language' or 'extlang'. Note that many of the prefixes for extended language subtags will have a 'Scope' of 'macrolanguage' (although some will not) and that many languages that have a 'Scope' of 'macrolanguage' will have extended language subtags associated with them.


The 'Scope' field MAY be added, modified, or removed via the registration process, provided the change mirrors changes made by ISO 639 to the assignment's classification. Such a change is expected to be rare.

“范围”字段可通过注册过程添加、修改或删除,前提是更改反映了ISO 639对分配分类所做的更改。这种变化预计将是罕见的。

For example, the primary language subtag 'zh' (Chinese) has a 'Scope' of 'macrolanguage', while its enclosed language 'nan' (Min Nan Chinese) has a 'Scope' of 'individual'. The special value 'und' (Undetermined) has a 'Scope' of 'special'. The ISO 639-5 collection 'gem' (Germanic languages) has a 'Scope' of 'collection'.

例如,初级语言子标签‘zh’(中文)的‘范围’为‘宏语言’,而其封闭语言‘南’(闽南中文)的‘范围’为‘个人’。特殊值“und”(未确定)的“范围”为“特殊”。ISO 639-5集合“gem”(日耳曼语言)的“范围”为“集合”。

3.1.12. Comments Field
3.1.12. 评论栏

The field 'Comments' contains additional information about the record and MAY appear more than once per record. The field-body MAY include the full range of Unicode characters and is not restricted to any particular script. This field MAY be inserted or changed via the registration process, and no guarantee of stability is provided.


The content of this field is not restricted, except by the need to register the information, the suitability of the request, and by reasonable practical size limitations. The primary reason for the 'Comments' field is subtag identification -- to help distinguish the subtag from others with which it might be confused as an aid to usage. Large amounts of information about the use, history, or general background of a subtag are frowned upon, as these generally belong in a registration request rather than in the registry.


3.2. Language Subtag Reviewer
3.2. 语言子标签评审员

The Language Subtag Reviewer moderates the mailing list, responds to requests for registration, and performs the other registry maintenance duties described in Section 3.3. Only the Language Subtag Reviewer is permitted to request IANA to change, update, or add records to the Language Subtag Registry. The Language Subtag Reviewer MAY delegate list moderation and other clerical duties as needed.


The Language Subtag Reviewer is appointed by the IESG for an indefinite term, subject to removal or replacement at the IESG's discretion. The IESG will solicit nominees for the position (upon adoption of this document or upon a vacancy) and then solicit feedback on the nominees' qualifications. Qualified candidates should be familiar with BCP 47 and its requirements; be willing to fairly, responsively, and judiciously administer the registration process; and be suitably informed about the issues of language identification so that the reviewer can assess the claims and draw upon the contributions of language experts and subtag requesters.

语言子标签审查员由IESG无限期任命,IESG可自行决定是否撤换。IESG将为该职位征求被提名人(在通过本文件或出现空缺时),然后征求被提名人资格的反馈意见。合格候选人应熟悉BCP 47及其要求;愿意公平、负责、明智地管理注册流程;并适当了解语言识别问题,以便审查人员能够评估索赔并利用语言专家和子标签请求者的贡献。

The subsequent performance or decisions of the Language Subtag Reviewer MAY be appealed to the IESG under the same rules as other IETF decisions (see [RFC2026]). The IESG can reverse or overturn the decisions of the Language Subtag Reviewer, provide guidance, or take other appropriate actions.


3.3. Maintenance of the Registry
3.3. 登记册的维持

Maintenance of the registry requires that, as codes are assigned or withdrawn by ISO 639, ISO 15924, ISO 3166, and UN M.49, the Language Subtag Reviewer MUST evaluate each change and determine the appropriate course of action according to the rules in this document. Such updates follow the registration process described in Section 3.5. Usually, the Language Subtag Reviewer will start the process for the new or updated record by filling in the registration form and submitting it. If a change to one of these standards takes place and the Language Subtag Reviewer does not do this in a timely manner, then any interested party MAY submit the form. Thereafter, the registration process continues normally.

登记册的维护要求,由于代码由ISO 639、ISO 15924、ISO 3166和UN M.49分配或撤销,语言子标签评审员必须根据本文件中的规则评估每次变更并确定适当的行动方案。此类更新遵循第3.5节所述的注册流程。通常,语言子标签评审员将通过填写登记表并提交来启动新记录或更新记录的流程。如果这些标准中的一项发生变更,且语言子标签评审员未及时进行变更,则任何相关方均可提交该表格。此后,注册过程继续正常进行。

Note that some registrations affect other subtags--perhaps more than one--as when a region subtag is being deprecated in favor of a new value. The Language Subtag Reviewer is responsible for ensuring that any such changes are properly registered, with each change requiring its own registration form.


The Language Subtag Reviewer MUST ensure that new subtags meet the requirements elsewhere in this document (and most especially in Section 3.4) or submit an appropriate registration form for an alternate subtag as described in that section. Each individual subtag affected by a change MUST be sent to the list with its own registration form and in a separate message.


3.4. Stability of IANA Registry Entries
3.4. IANA注册表项的稳定性

The stability of entries and their meaning in the registry is critical to the long-term stability of language tags. The rules in this section guarantee that a specific language tag's meaning is stable over time and will not change.


These rules specifically deal with how changes to codes (including withdrawal and deprecation of codes) maintained by ISO 639, ISO 15924, ISO 3166, and UN M.49 are reflected in the IANA Language Subtag Registry. Assignments to the IANA Language Subtag Registry MUST follow the following stability rules:

这些规则专门处理ISO 639、ISO 15924、ISO 3166和UN M.49维护的代码更改(包括代码的撤销和弃用)如何反映在IANA语言子标记注册表中。IANA语言子标记注册表的分配必须遵循以下稳定性规则:

1. Values in the fields 'Type', 'Subtag', 'Tag', and 'Added' MUST NOT be changed and are guaranteed to be stable over time.

1. “Type”、“Subtag”、“Tag”和“Added”字段中的值不得更改,并保证随着时间的推移保持稳定。

2. Values in the fields 'Preferred-Value' and 'Deprecated' MAY be added, altered, or removed via the registration process. These changes SHOULD be limited to changes necessary to mirror changes in one of the underlying standards (ISO 639, ISO 15924, ISO 3166-1, or UN M.49) and typically alteration or removal of a 'Preferred-Value' is limited specifically to region codes.

2. “首选值”和“不推荐”字段中的值可以通过注册过程添加、更改或删除。这些变更应限于反映一项基本标准(ISO 639、ISO 15924、ISO 3166-1或UN M.49)变更所需的变更,并且“首选值”的变更或删除通常仅限于地区代码。

3. Values in the 'Description' field MUST NOT be changed in a way that would invalidate any existing tags. The description MAY be broadened somewhat in scope, changed to add information, or adapted to the most common modern usage. For example, countries occasionally change their names; a historical example of this is "Upper Volta" changing to "Burkina Faso".

3. “Description”字段中的值不得以使任何现有标记无效的方式进行更改。描述的范围可能会有所扩大,更改以添加信息,或者适应最常见的现代用法。例如,国家偶尔会更名;历史上的一个例子是“上沃尔特”改为“布基纳法索”。

4. Values in the field 'Prefix' MAY be added to existing records of type 'variant' via the registration process, provided the 'variant' already has at least one 'Prefix'. A 'Prefix' field SHALL NOT be registered for any 'variant' that has no existing 'Prefix' field. If a prefix is added to a variant record, 'Comment' fields MAY be used to explain different usages with the various prefixes.

4. “Prefix”字段中的值可以通过注册过程添加到“variant”类型的现有记录中,前提是“variant”已经至少有一个“Prefix”。对于没有“前缀”字段的任何“变体”,不得注册“前缀”字段。若在变量记录中添加前缀,“注释”字段可用于解释不同前缀的不同用法。

5. Values in the field 'Prefix' in records of type 'variant' MAY also be modified, so long as the modifications broaden the set of prefixes. That is, a prefix MAY be replaced by one of its own prefixes. For example, the prefix "en-US" could be replaced by "en", but not by the prefixes "en-Latn", "fr", or "en-US-boont". If one of those prefix values were needed, it would have to be separately registered.

5. “variant”类型记录中“Prefix”字段中的值也可以修改,只要修改扩展了前缀集。也就是说,一个前缀可以被它自己的一个前缀替换。例如,前缀“en US”可以替换为“en”,但不能替换为前缀“en Latn”、“fr”或“en US boont”。如果需要其中一个前缀值,则必须单独注册。

6. Values in the field 'Prefix' in records of type 'extlang' MUST NOT be added, modified, or removed.

6. 不得添加、修改或删除“extlang”类型记录中“Prefix”字段中的值。

7. The field 'Prefix' MUST NOT be removed from any record in which it appears. This field SHOULD be included in the initial registration of any records of type 'variant' and MUST be included in any records of type 'extlang'.

7. “Prefix”字段不能从其出现的任何记录中删除。此字段应包含在任何“variant”类型记录的初始注册中,并且必须包含在任何“extlang”类型记录中。

8. The field 'Comments' MAY be added, changed, modified, or removed via the registration process or any of the processes or considerations described in this section.

8. 可通过注册流程或本节所述的任何流程或注意事项添加、更改、修改或删除“注释”字段。

9. The field 'Suppress-Script' MAY be added or removed via the registration process.

9. “抑制脚本”字段可以通过注册过程添加或删除。

10. The field 'Macrolanguage' MAY be added or removed via the registration process, but only in response to changes made by ISO 639. The 'Macrolanguage' field appears whenever a language has a corresponding macrolanguage in ISO 639. That is, the 'Macrolanguage' fields in the registry exactly match those of ISO 639. No other macrolanguage mappings will be considered for registration.

10. “宏语言”字段可以通过注册过程添加或删除,但只能响应ISO 639所做的更改。每当一种语言在ISO 639中有相应的宏语言时,“宏语言”字段就会出现。也就是说,注册表中的“宏语言”字段与ISO 639中的字段完全匹配。注册时不考虑其他宏语言映射。

11. The field 'Scope' MAY be added or removed from a primary or extended language subtag after initial registration, and it MAY be modified in order to match any changes made by ISO 639. Changes to the 'Scope' field MUST mirror changes made by ISO 639. Note that primary or extended language subtags whose records do not contain a 'Scope' field (that is, most of them) are individual languages as described in Section 3.1.11.

11. 初始注册后,可在主语言或扩展语言子标签中添加或删除“范围”字段,并可对其进行修改,以匹配ISO 639所做的任何更改。“范围”字段的更改必须反映ISO 639所做的更改。请注意,其记录不包含“范围”字段的主语言或扩展语言子标签(即大多数)是第3.1.11节所述的单独语言。

12. Primary and extended language subtags (other than independently registered values created using the registration process) are created according to the assignments of the various parts of ISO 639, as follows:

12. 主要和扩展语言子标签(使用注册过程创建的独立注册值除外)根据ISO 639各部分的分配创建,如下所示:

A. Codes assigned by ISO 639-1 that do not conflict with existing two-letter primary language subtags and that have no corresponding three-letter primary defined in the registry are entered into the IANA registry as new records

A.由ISO 639-1分配的代码,如果与现有的两个字母主语言子标签不冲突,并且没有在注册表中定义相应的三个字母主语言子标签,则作为新记录输入IANA注册表

of type 'language'. Note that languages given an ISO 639-1 code cannot be given extended language subtags, even if encompassed by a macrolanguage.

属于“语言”类型。请注意,给定ISO 639-1代码的语言不能被赋予扩展语言子标签,即使包含在宏语言中。

B. Codes assigned by ISO 639-3 or ISO 639-5 that do not conflict with existing three-letter primary language subtags and that do not have ISO 639-1 codes assigned (or expected to be assigned) are entered into the IANA registry as new records of type 'language'. Note that these two standards now comprise a superset of ISO 639-2 codes. Codes that have a defined 'macrolanguage' mapping at the time of their registration MUST contain a 'Macrolanguage' field.

B.ISO 639-3或ISO 639-5分配的代码与现有三字母主语言子标签不冲突,且未分配(或预期分配)ISO 639-1代码,作为“语言”类型的新记录输入IANA注册表。请注意,这两个标准现在包含ISO 639-2代码的超集。注册时已定义“宏语言”映射的代码必须包含“宏语言”字段。

C. Codes assigned by ISO 639-3 MAY also be considered for an extended language subtag registration. Note that they MUST be assigned a primary language subtag record of type 'language' even when an 'extlang' record is proposed. When considering extended language subtag assignment, these criteria apply:

C.ISO 639-3指定的代码也可考虑用于扩展语言子标签注册。请注意,即使建议使用“extlang”记录,也必须为它们分配类型为“language”的主语言子标记记录。当考虑扩展语言子标签分配时,以下标准适用:

1. If a language has a macrolanguage mapping, and that macrolanguage has other encompassed languages that are assigned extended language subtags, then the new language SHOULD have an 'extlang' record assigned to it as well. For example, any language with a macrolanguage of 'zh' or 'ar' would be assigned an 'extlang' record.

1. 如果一种语言有一个宏语言映射,并且该宏语言有其他被分配了扩展语言子标签的包含语言,那么新语言也应该有一个分配给它的“extlang”记录。例如,任何宏语言为'zh'或'ar'的语言都将被分配一个'extlang'记录。

2. 'Extlang' records SHOULD NOT be created for languages if other languages encompassed by the macrolanguage do not also include 'extlang' records. For example, if a new Serbo-Croatian ('sh') language were registered, it would not get an extlang record because other languages encompassed, such as Serbian ('sr'), do not include one in the registry.

2. 如果宏语言包含的其他语言不包括“Extlang”记录,则不应为这些语言创建“Extlang”记录。例如,如果注册了一种新的塞尔维亚-克罗地亚语(“sh”)语言,它将不会获得extlang记录,因为所包含的其他语言,如塞尔维亚语(“sr”)在注册中不包含extlang记录。

3. Sign languages SHOULD have an 'extlang' record with a 'Prefix' of 'sgn'.

3. 手语应该有一个“extlang”记录,其“前缀”为“sgn”。

4. 'Extlang' records MUST NOT be created for items already in the registry. Extended language subtags will only be considered at the time of initial registration.

4. 不能为注册表中已有的项创建“Extlang”记录。扩展语言子标签仅在初次注册时考虑。

5. Extended language subtag records MUST include the fields 'Prefix' and 'Preferred-Value' with field values assigned as described in Section 2.2.2.

5. 扩展语言子标记记录必须包括字段“前缀”和“首选值”,并按照第2.2.2节所述分配字段值。

D. Any other codes assigned by ISO 639-2 that do not conflict with existing three-letter primary or extended language

D.ISO 639-2指定的与现有三字母主语言或扩展语言不冲突的任何其他代码

subtags and that do not have ISO 639-1 two-letter codes assigned are entered into the IANA registry as new records of type 'language'. This type of registration is not supposed to occur in the future.

未分配ISO 639-1双字母代码的子标签和子标签作为“语言”类型的新记录输入IANA注册表。这种类型的注册不应该在将来发生。

13. Codes assigned by ISO 15924 and ISO 3166-1 that do not conflict with existing subtags of the associated type and whose meaning is not the same as an existing subtag of the same type are entered into the IANA registry as new records.

13. ISO 15924和ISO 3166-1分配的代码与相关类型的现有子标签不冲突,且其含义与相同类型的现有子标签不相同,作为新记录输入IANA注册表。

14. Codes assigned by ISO 639, ISO 15924, or ISO 3166-1 that are withdrawn by their respective maintenance or registration authority remain valid in language tags. A 'Deprecated' field containing the date of withdrawal MUST be added to the record. If a new record of the same type is added that represents a replacement value, then a 'Preferred-Value' field MAY also be added. The registration process MAY be used to add comments about the withdrawal of the code by the respective standard.

14. 由ISO 639、ISO 15924或ISO 3166-1分配的代码(由各自的维护或注册机构撤销)在语言标签中仍然有效。必须将包含提取日期的“弃用”字段添加到记录中。如果添加了表示替换值的相同类型的新记录,则还可以添加“首选值”字段。注册过程可用于添加关于各标准撤销代码的注释。

For example: the region code 'TL' was assigned to the country 'Timor-Leste', replacing the code 'TP' (which was assigned to 'East Timor' when it was under administration by Portugal). The subtag 'TP' remains valid in language tags, but its record contains the 'Preferred-Value' of 'TL' and its field 'Deprecated' contains the date the new code was assigned ('2004-07-06').


15. Codes assigned by ISO 639, ISO 15924, or ISO 3166-1 that conflict with existing subtags of the associated type, including subtags that are deprecated, MUST NOT be entered into the registry. The following additional considerations apply to subtag values that are reassigned:

15. 由ISO 639、ISO 15924或ISO 3166-1分配的与关联类型的现有子标记(包括不推荐使用的子标记)冲突的代码不得输入注册表。以下附加注意事项适用于重新分配的子标记值:

A. For ISO 639 codes, if the newly assigned code's meaning is not represented by a subtag in the IANA registry, the Language Subtag Reviewer, as described in Section 3.5, SHALL prepare a proposal for entering in the IANA registry, as soon as practical, a registered language subtag as an alternate value for the new code. The form of the registered language subtag will be at the discretion of the Language Subtag Reviewer and MUST conform to other restrictions on language subtags in this document.

A.对于ISO 639代码,如果IANA注册中心中的子标签未表示新分配代码的含义,则第3.5节中所述的语言子标签审查员应编制一份建议书,以尽快在IANA注册中心输入注册语言子标签,作为新代码的替代值。注册语言子标签的格式将由语言子标签审查员自行决定,并且必须符合本文件中对语言子标签的其他限制。

B. For all subtags whose meaning is derived from an external standard (that is, by ISO 639, ISO 15924, ISO 3166-1, or UN M.49), if a new meaning is assigned to an existing code and the new meaning broadens the meaning of that code, then the meaning for the associated subtag MAY be changed to match.

B.对于含义源自外部标准(即ISO 639、ISO 15924、ISO 3166-1或UN M.49)的所有子标签,如果对现有代码赋予了新含义,且新含义扩大了该代码的含义,则相关子标签的含义可能会更改为匹配。

The meaning of a subtag MUST NOT be narrowed, however, as this can result in an unknown proportion of the existing uses of a subtag becoming invalid. Note: the ISO 639 registration authority (RA) has adopted a similar stability policy.

但是,子标签的含义不能缩小,因为这可能导致子标签现有使用中未知比例的无效。注:ISO 639注册管理局(RA)采用了类似的稳定性政策。

C. For ISO 15924 codes, if the newly assigned code's meaning is not represented by a subtag in the IANA registry, the Language Subtag Reviewer, as described in Section 3.5, SHALL prepare a proposal for entering in the IANA registry, as soon as practical, a registered variant subtag as an alternate value for the new code. The form of the registered variant subtag will be at the discretion of the Language Subtag Reviewer and MUST conform to other restrictions on variant subtags in this document.

C.对于ISO 15924代码,如果新分配代码的含义未由IANA注册中心的子标签表示,则语言子标签审查员(如第3.5节所述)应编制一份建议书,以尽快在IANA注册中心输入一个注册变体子标签,作为新代码的替代值。注册变体子标签的格式将由语言子标签审查员决定,并且必须符合本文件中关于变体子标签的其他限制。

D. For ISO 3166-1 codes, if the newly assigned code's meaning is associated with the same UN M.49 code as another 'region' subtag, then the existing region subtag remains as the preferred value for that region and no new entry is created. A comment MAY be added to the existing region subtag indicating the relationship to the new ISO 3166-1 code.

D.对于ISO 3166-1代码,如果新分配代码的含义与另一个“区域”子标记相同的UN M.49代码相关联,则现有区域子标记保留为该区域的首选值,并且不会创建新条目。可在现有区域子标记中添加注释,指示与新ISO 3166-1代码的关系。

E. For ISO 3166-1 codes, if the newly assigned code's meaning is associated with a UN M.49 code that is not represented by an existing region subtag, then the Language Subtag Reviewer, as described in Section 3.5, SHALL prepare a proposal for entering the appropriate UN M.49 country code as an entry in the IANA registry.

E.对于ISO 3166-1代码,如果新分配的代码的含义与UN M.49代码相关,而该代码未由现有区域子标签表示,则语言子标签审查员(如第3.5节所述)应编制一份建议书,将适当的UN M.49国家代码作为条目输入IANA登记册。

F. For ISO 3166-1 codes, if there is no associated UN numeric code, then the Language Subtag Reviewer SHALL petition the UN to create one. If there is no response from the UN within 90 days of the request being sent, the Language Subtag Reviewer SHALL prepare a proposal for entering in the IANA registry, as soon as practical, a registered variant subtag as an alternate value for the new code. The form of the registered variant subtag will be at the discretion of the Language Subtag Reviewer and MUST conform to other restrictions on variant subtags in this document. This situation is very unlikely to ever occur.

F.对于ISO 3166-1代码,如果没有相关的联合国数字代码,则语言子标签评审员应请求联合国创建一个。如果在发出请求后90天内未收到联合国的回复,则语言子标签审查员应编制一份建议书,以便在可行的情况下尽快将注册的变体子标签输入IANA注册中心,作为新代码的替代值。注册变体子标签的格式将由语言子标签审查员决定,并且必须符合本文件中关于变体子标签的其他限制。这种情况不太可能发生。

16. UN M.49 has codes for both "countries and areas" (such as '276' for Germany) and "geographical regions and sub-regions" (such as '150' for Europe). UN M.49 country or area codes for which there is no corresponding ISO 3166-1 code MUST NOT be registered, except as a surrogate for an ISO 3166-1 code that is blocked from registration by an existing subtag.

16. UN M.49既有“国家和地区”(如德国的“276”)代码,也有“地理区域和次区域”(如欧洲的“150”)代码。UN M.49没有相应ISO 3166-1代码的国家或地区代码不得注册,除非作为ISO 3166-1代码的替代物,该代码被现有子标记阻止注册。

If such a code becomes necessary, then the maintenance agency for ISO 3166-1 SHALL first be petitioned to assign a code to the region. If the petition for a code assignment by ISO 3166-1 is refused or not acted on in a timely manner, the registration process described in Section 3.5 can then be used to register the corresponding UN M.49 code. This way, UN M.49 codes remain available as the value of last resort in cases where ISO 3166-1 reassigns a deprecated value in the registry.

如果需要此类代码,则应首先请求ISO 3166-1维护机构为该地区指定代码。如果ISO 3166-1的代码分配申请被拒绝或未及时采取行动,则可使用第3.5节中描述的注册过程注册相应的UN M.49代码。这样,当ISO 3166-1在注册表中重新分配不推荐的值时,UN M.49代码仍然可用作最后手段的值。

17. The redundant and grandfathered entries together form the complete list of tags registered under [RFC3066]. The redundant tags are those previously registered tags that can now be formed using the subtags defined in the registry. The grandfathered entries include those that can never be legal because they are 'irregular' (that is, they do not match the 'langtag' production in Figure 1), are limited by rule (subtags such as 'nyn' and 'min' look like the extlang production, but cannot be registered as extended language subtags), or their subtags are inappropriate for registration. All of the grandfathered tags are listed in either the 'regular' or the 'irregular' productions in the ABNF. Under [RFC4646] it was possible for grandfathered tags to become redundant. However, all of the tags for which this was possible became redundant before this document was produced. So the set of redundant and grandfathered tags is now permanent and immutable: new entries of either type MUST NOT be added and existing entries MUST NOT be removed. The decision-making process about which tags were initially grandfathered and which were made redundant is described in [RFC4645].

17. 冗余项和冗余项一起构成了在[RFC3066]下注册的标签的完整列表。冗余标记是以前注册的标记,现在可以使用注册表中定义的子标记来形成这些标记。grandfathered条目包括那些永远不会合法的条目,因为它们是“不规则的”(即,它们与图1中的“langtag”产品不匹配),受规则限制(子标签如“nyn”和“min”看起来像extlang产品,但不能注册为扩展语言子标签),或其子标签不适合注册。ABNF中的“常规”或“非常规”产品中列出了所有祖辈标签。在[RFC4646]下,祖父标记可能变得多余。然而,在本文档生成之前,所有可能的标签都变得多余。因此,这组冗余的和祖父标记现在是永久不变的:任何一种类型的新条目都不能添加,现有条目也不能删除。[RFC4645]中描述了关于哪些标签最初被赋予祖父权,哪些标签被赋予冗余权的决策过程。

Many of the grandfathered tags are deprecated -- indeed, they were deprecated even before [RFC4646]. For example, the tag "art-lojban" was deprecated in favor of the primary language subtag 'jbo'. These tags could have been made 'redundant' by registering some of their subtags as 'variants'. The 'variant-like' subtags in the grandfathered registrations SHALL NOT be registered in the future, even with a similar or identical meaning.

许多grandfathered标记都已弃用——事实上,它们甚至在[RFC4646]之前就已经弃用了。例如,标签“art lojban”被弃用,取而代之的是主语言子标签“jbo”。这些标签可以通过将一些子标签注册为“变体”而变得“多余”。祖辈注册中的“类似变体”子标签今后不得注册,即使具有类似或相同的含义。

3.5. Registration Procedure for Subtags
3.5. 子标签的注册程序

The procedure given here MUST be used by anyone who wants to use a subtag not currently in the IANA Language Subtag Registry or who wishes to add, modify, update, or remove information in existing records as permitted by this document.


Only subtags of type 'language' and 'variant' will be considered for independent registration of new subtags. Subtags needed for


stability and subtags necessary to keep the registry synchronized with ISO 639, ISO 15924, ISO 3166, and UN M.49 within the limits defined by this document also use this process, as described in Section 3.3 and subject to stability provisions as described in Section 3.4.

如第3.3节所述,保持注册表与ISO 639、ISO 15924、ISO 3166和UN M.49在本文件规定的范围内同步所需的稳定性和子标签也使用此过程,并遵守第3.4节所述的稳定性规定。

Registration requests are accepted relating to information in the 'Comments', 'Deprecated', 'Description', 'Prefix', 'Preferred-Value', 'Macrolanguage', or 'Suppress-Script' fields in a subtag's record as described in Section 3.4. Changes to all other fields in the IANA registry are NOT permitted.


Registering a new subtag or requesting modifications to an existing tag or subtag starts with the requester filling out the registration form reproduced below. Note that each response is not limited in size so that the request can adequately describe the registration. The fields in the "Record Requested" section need to follow the requirements in Section 3.1 before the record will be approved.


LANGUAGE SUBTAG REGISTRATION FORM 1. Name of requester: 2. E-mail address of requester: 3. Record Requested:


Type: Subtag: Description: Prefix: Preferred-Value: Deprecated: Suppress-Script: Macrolanguage: Comments:


4. Intended meaning of the subtag: 5. Reference to published description of the language (book or article): 6. Any other relevant information:

4. 子标签的预期含义:5。参考已出版的语言描述(书或文章):6。任何其他相关信息:

Figure 5: The Language Subtag Registration Form


Examples of completed registration forms can be found in Appendix B. A complete list of approved registration forms is online through; readers should note that the Language Tag Registry is now obsolete and should instead look for the Language Subtag Registry.

已填妥的注册表格示例见附录B。已批准注册表格的完整列表可通过; 读者应该注意,语言标记注册表现在已经过时,应该查找语言子标记注册表。

The subtag registration form MUST be sent to <>. Registration requests receive a two-week review period before being approved and submitted to IANA for inclusion in the registry. If modifications are made to the request during the course of the registration process (such as corrections to meet the requirements in Section 3.1 or to make the 'Description' fields unique for the given record type), the modified form MUST also be sent to <> at least one week prior to submission to IANA.

子标签登记表必须发送至<>. 注册申请在获得批准并提交给IANA以纳入注册中心之前,需要两周的审查期。如果在注册过程中对请求进行了修改(如修改以满足第3.1节的要求或使“描述”字段对给定记录类型唯一),修改后的表格也必须发送至<>提交给IANA前至少一周。

The ietf-languages list is an open list and can be joined by sending a request to <>. The list can be hosted by IANA or any third party at the request of IESG.

ietf语言列表是一个开放列表,可以通过向<ietf语言发送请求来加入>. 应IESG的要求,IANA或任何第三方均可托管该列表。

Before forwarding any registration to IANA, the Language Subtag Reviewer MUST ensure that all requirements in this document are met. This includes ensuring that values in the 'Subtag' field match case according to the description in Section 3.1.4 and that 'Description' fields are unique for the given record type as described in Section 3.1.5. The Reviewer MUST also ensure that an appropriate File-Date record is included in the request, to assist IANA when updating the registry (see Section 5.1).


Some fields in both the registration form as well as the registry record itself permit the use of non-ASCII characters. Registration requests SHOULD use the UTF-8 encoding for consistency and clarity. However, since some mail clients do not support this encoding, other encodings MAY be used for the registration request. The Language Subtag Reviewer is responsible for ensuring that the proper Unicode characters appear in both the archived request form and the registry record. In the case of a transcription or encoding error by IANA, the Language Subtag Reviewer will request that the registry be repaired, providing any necessary information to assist IANA.

登记表中的某些字段以及注册表记录本身都允许使用非ASCII字符。注册请求应使用UTF-8编码,以确保一致性和清晰性。但是,由于某些邮件客户端不支持此编码,因此可以对注册请求使用其他编码。Language Subtag Reviewer负责确保在存档的请求表单和注册表记录中显示正确的Unicode字符。如果IANA出现转录或编码错误,语言子标签审查员将要求修复注册表,并提供任何必要的信息以协助IANA。

Extended language subtags (type 'extlang'), by definition, are always encompassed by another language. All records of type 'extlang' MUST, therefore, contain a 'Prefix' field at the time of registration. This 'Prefix' field can never be altered or removed, and requests to do so MUST be rejected.


Variant subtags are usually registered for use with a particular range of language tags, and variant subtags based on the terminology of the language to which they are apply are encouraged. For example, the subtag 'rozaj' (Resian) is intended for use with language tags that start with the primary language subtag "sl" (Slovenian), since Resian is a dialect of Slovenian. Thus, the subtag 'rozaj' would be appropriate in tags such as "sl-Latn-rozaj" or "sl-IT-rozaj". This information is stored in the 'Prefix' field in the registry. Variant

变体子标签通常注册用于特定范围的语言标签,并且鼓励基于所应用语言术语的变体子标签。例如,子标记“rozaj”(Resian)用于以主要语言子标记“sl”(斯洛文尼亚语)开头的语言标记,因为Resian是斯洛文尼亚方言。因此,子标签“rozaj”适用于“sl Latn rozaj”或“sl IT rozaj”等标签。此信息存储在注册表的“前缀”字段中。变种

registration requests SHOULD include at least one 'Prefix' field in the registration form.


Requests to assign an additional record of a given type with an existing subtag value MUST be rejected. For example, the variant subtag 'rozaj' already exists in the registry, so adding a second record of type 'variant' with the subtag 'rozaj' is prohibited.


The 'Prefix' field for a given registered variant subtag exists in the IANA registry as a guide to usage. Additional 'Prefix' fields MAY be added by filing an additional registration form. In that form, the "Any other relevant information:" field MUST indicate that it is the addition of a prefix.


Requests to add a 'Prefix' field to a variant subtag that imply a different semantic meaning SHOULD be rejected. For example, a request to add the prefix "de" to the subtag '1994' so that the tag "de-1994" represented some German dialect or orthographic form would be rejected. The '1994' subtag represents a particular Slovenian orthography, and the additional registration would change or blur the semantic meaning assigned to the subtag. A separate subtag SHOULD be proposed instead.


Requests to add a 'Prefix' to a variant subtag that has no current 'Prefix' field MUST be rejected. Variants are registered with no prefix because they are potentially useful with many or even all languages. Adding one or more 'Prefix' fields would be potentially harmful to the use of the variant, since it dramatically reduces the scope of the subtag (which is not allowed under the stability rules (Section 3.4) as opposed to broadening the scope of the subtag, which is what the addition of a 'Prefix' normally does. An example of such a "no-prefix" variant is the subtag 'fonipa', which represents the International Phonetic Alphabet, a scheme that can be used to transcribe many languages.


The 'Description' fields provided in the request MUST contain at least one description written or transcribed into the Latin script; the request MAY also include additional 'Description' fields in any script or language. The 'Description' field is used for identification purposes and doesn't necessarily represent the actual native name of the language or variation. It also doesn't have to be in any particular language, but SHOULD be both suitable and sufficient to identify the item in the record. The Language Subtag Reviewer will check and edit any proposed 'Description' fields so as to ensure uniqueness and prevent collisions with 'Description' fields in other records of the same type. If this occurs in an independent registration request, the Language Subtag Reviewer MUST resubmit the record to <>, treating it as a modification of


a request due to discussion, as described in Section 3.5, unless the request's sole purpose is to introduce a duplicate 'Description' field, in which case the request SHALL be rejected.


The 'Description' field is not guaranteed to be stable. Corrections or clarifications of intent are examples of possible changes. Attempts to provide translations or transcriptions of entries in the registry (which, by definition, provide no new information) are unlikely to be approved.


Soon after the two-week review period has passed, the Language Subtag Reviewer MUST take one of the following actions:


o Explicitly accept the request and forward the form containing the record to be inserted or modified to <> according to the procedure described in Section 3.3.

o 显式接受请求并将包含要插入或修改的记录的表单转发到<>根据第3.3节所述的程序。

o Explicitly reject the request because of significant objections raised on the list or due to problems with constraints in this document (which MUST be explicitly cited).

o 由于清单上提出的重大反对意见或本文件中的约束问题(必须明确引用),明确拒绝请求。

o Extend the review period by granting an additional two-week increment to permit further discussion. After each two-week increment, the Language Subtag Reviewer MUST indicate on the list whether the registration has been accepted, rejected, or extended.

o 延长审查期,给予额外的两周增量,以便进一步讨论。每增加两周后,语言子标签评审员必须在列表上指出注册是否已被接受、拒绝或延长。

Note that the Language Subtag Reviewer MAY raise objections on the list if he or she so desires. The important thing is that the objection MUST be made publicly.


Sometimes the request needs to be modified as a result of discussion during the review period or due to requirements in this document. The applicant, Language Subtag Reviewer, or others MAY submit a modified version of the completed registration form, which will be considered in lieu of the original request with the explicit approval of the applicant. Such changes do not restart the two-week discussion period, although an application containing the final record submitted to IANA MUST appear on the list at least one week prior to the Language Subtag Reviewer forwarding the record to IANA. The applicant MAY modify a rejected application with more appropriate or additional information and submit it again; this starts a new two-week comment period.


Registrations initiated due to the provisions of Section 3.3 or Section 3.4 SHALL NOT be rejected altogether (since they have to ultimately appear in the registry) and SHOULD be completed as quickly as possible. The review process allows list members to comment on the specific information in the form and the record it contains and


thus help ensure that it is correct and consistent. The Language Subtag Reviewer MAY reject a specific version of the form, but MUST propose a suitable replacement, extending the review period as described above, until the form is in a format worthy of the reviewer's approval and meets with rough consensus of the list.


Decisions made by the Language Subtag Reviewer MAY be appealed to the IESG [RFC2028] under the same rules as other IETF decisions [RFC2026]. This includes a decision to extend the review period or the failure to announce a decision in a clear and timely manner.


The approved records appear in the Language Subtag Registry. The approved registration forms are available online from


Updates or changes to existing records follow the same procedure as new registrations. The Language Subtag Reviewer decides whether there is consensus to update the registration following the two-week review period; normally, objections by the original registrant will carry extra weight in forming such a consensus.


Registrations are permanent and stable. Once registered, subtags will not be removed from the registry and will remain a valid way in which to specify a specific language or variant.


Note: The purpose of the "Reference to published description" section in the registration form is to aid in verifying whether a language is registered or to which language or language variation a particular subtag refers. In most cases, reference to an authoritative grammar or dictionary of that language will be useful; in cases where no such work exists, other well-known works describing that language or in that language MAY be appropriate. The Language Subtag Reviewer decides what constitutes "good enough" reference material. This requirement is not intended to exclude particular languages or dialects due to the size of the speaker population or lack of a standardized orthography. Minority languages will be considered equally on their own merits.


3.6. Possibilities for Registration
3.6. 登记的可能性

Possibilities for registration of subtags or information about subtags include:


o Primary language subtags for languages not listed in ISO 639 that are not variants of any listed or registered language MAY be registered. At the time this document was created, there were no examples of this form of subtag. Before attempting to register a language subtag, there MUST be an attempt to register the language

o 可以注册ISO 639中未列出的语言的主语言子标签,这些语言不是任何列出或注册语言的变体。在创建此文档时,没有这种形式的子标签的示例。在尝试注册语言子标记之前,必须尝试注册该语言

with ISO 639. Subtags MUST NOT be registered for languages defined by codes that exist in ISO 639-1, ISO 639-2, or ISO 639-3; that are under consideration by the ISO 639 registration authorities; or that have never been attempted for registration with those authorities. If ISO 639 has previously rejected a language for registration, it is reasonable to assume that there must be additional, very compelling evidence of need before it will be registered as a primary language subtag in the IANA registry (to the extent that it is very unlikely that any subtags will be registered of this type).

符合ISO 639标准。对于ISO 639-1、ISO 639-2或ISO 639-3中存在的代码定义的语言,不得注册子标签;ISO 639注册机构正在考虑的;或者从未尝试在这些机构注册。如果ISO 639之前拒绝了一种语言的注册,那么可以合理地假设,在将其注册为IANA注册中心的主要语言子标签之前,必须有额外的、非常令人信服的需求证据(在一定程度上,任何子标签都不太可能注册为这种类型)。

o Dialect or other divisions or variations within a language, its orthography, writing system, regional or historical usage, transliteration or other transformation, or distinguishing variation MAY be registered as variant subtags. An example is the 'rozaj' subtag (the Resian dialect of Slovenian).

o 方言或一种语言中的其他分支或变体、其正字法、书写系统、区域或历史用法、音译或其他转换,或区别变体,可登记为变体子标签。例如,“rozaj”子标签(斯洛文尼亚的Resian方言)。

o The addition or maintenance of fields (generally of an informational nature) in tag or subtag records as described in Section 3.1 is allowed. Such changes are subject to the stability provisions in Section 3.4. This includes 'Description', 'Comments', 'Deprecated', and 'Preferred-Value' fields for obsolete or withdrawn codes, or the addition of 'Suppress-Script' or 'Macrolanguage' fields to primary language subtags, as well as other changes permitted by this document, such as the addition of an appropriate 'Prefix' field to a variant subtag.

o 允许在标签或子标签记录中添加或维护第3.1节所述的字段(通常为信息性字段)。此类变更应遵守第3.4节中的稳定性规定。这包括过时或撤销代码的“说明”、“注释”、“弃用”和“首选值”字段,或在主语言子标记中添加“抑制脚本”或“宏语言”字段,以及本文档允许的其他更改,例如在变体子标记中添加适当的“前缀”字段。

o The addition of records and related field value changes necessary to reflect assignments made by ISO 639, ISO 15924, ISO 3166-1, and UN M.49 as described in Section 3.4 is allowed.

o 允许添加记录和相关字段值更改,以反映第3.4节所述的ISO 639、ISO 15924、ISO 3166-1和UN M.49的赋值。

Subtags proposed for registration that would cause all or part of a grandfathered tag to become redundant but whose meaning conflicts with or alters the meaning of the grandfathered tag MUST be rejected.


This document leaves the decision on what subtags or changes to subtags are appropriate (or not) to the registration process described in Section 3.5.


Note: Four-character primary language subtags are reserved to allow for the possibility of alpha4 codes in some future addition to the ISO 639 family of standards.

注:保留了四个字符的主语言子标签,以允许将来在ISO 639标准系列中添加alpha4代码。

ISO 639 defines a registration authority for additions to and changes in the list of languages in ISO 639. This agency is:

ISO 639为ISO 639中语言列表的添加和更改定义了注册机构。该机构是:

International Information Centre for Terminology (Infoterm) Aichholzgasse 6/12, AT-1120 Wien, Austria Phone: +43 1 26 75 35 Ext. 312 Fax: +43 1 216 32 72

国际术语信息中心(Infoterm)Aichholzgasse 6/12,地址:奥地利维恩1120电话:+43 1 26 75 35分机312传真:+43 1 216 32 72

ISO 639-2 defines a registration authority for additions to and changes in the list of languages in ISO 639-2. This agency is:

ISO 639-2定义了ISO 639-2中语言列表添加和更改的注册机构。该机构是:

   Library of Congress
   Network Development and MARC Standards Office
   Washington, DC 20540, USA
   Phone: +1 202 707 6237 Fax: +1 202 707 0115
   Library of Congress
   Network Development and MARC Standards Office
   Washington, DC 20540, USA
   Phone: +1 202 707 6237 Fax: +1 202 707 0115

ISO 639-3 defines a registration authority for additions to and changes in the list of languages in ISO 639-3. This agency is:

ISO 639-3定义了ISO 639-3中语言列表添加和更改的注册机构。该机构是:

   SIL International
   ISO 639-3 Registrar
   7500 W. Camp Wisdom Rd.
   Dallas, TX 75236, USA
   Phone: +1 972 708 7400, ext. 2293
   Fax: +1 972 708 7546
   SIL International
   ISO 639-3 Registrar
   7500 W. Camp Wisdom Rd.
   Dallas, TX 75236, USA
   Phone: +1 972 708 7400, ext. 2293
   Fax: +1 972 708 7546

ISO 639-5 defines a registration authority for additions to and changes in the list of languages in ISO 639-5. This agency is the same as for ISO 639-2 and is:

ISO 639-5定义了ISO 639-5中语言列表添加和更改的注册机构。该机构与ISO 639-2相同,是:

   Library of Congress
   Network Development and MARC Standards Office
   Washington, DC 20540, USA
   Phone: +1 202 707 6237
   Fax: +1 202 707 0115
   Library of Congress
   Network Development and MARC Standards Office
   Washington, DC 20540, USA
   Phone: +1 202 707 6237
   Fax: +1 202 707 0115

The maintenance agency for ISO 3166-1 (country codes) is:

ISO 3166-1(国家代码)的维护机构为:

   ISO 3166 Maintenance Agency
   c/o International Organization for Standardization
   Case postale 56
   CH-1211 Geneva 20, Switzerland
   Phone: +41 22 749 72 33 Fax: +41 22 749 73 49
   ISO 3166 Maintenance Agency
   c/o International Organization for Standardization
   Case postale 56
   CH-1211 Geneva 20, Switzerland
   Phone: +41 22 749 72 33 Fax: +41 22 749 73 49

The registration authority for ISO 15924 (script codes) is:

ISO 15924(脚本代码)的注册机构为:

Unicode Consortium Box 391476 Mountain View, CA 94039-1476, USA URL:

Unicode联合体信箱391476美国加利福尼亚州山景城94039-1476 URL:

The Statistics Division of the United Nations Secretariat maintains the Standard Country or Area Codes for Statistical Use and can be reached at:


   Statistical Services Branch
   Statistics Division
   United Nations, Room DC2-1620
   New York, NY 10017, USA
   Fax: +1-212-963-0623
   Statistical Services Branch
   Statistics Division
   United Nations, Room DC2-1620
   New York, NY 10017, USA
   Fax: +1-212-963-0623
3.7. Extensions and the Extensions Registry
3.7. 扩展和扩展注册表

Extension subtags are those introduced by single-character subtags ("singletons") other than 'x'. They are reserved for the generation of identifiers that contain a language component and are compatible with applications that understand language tags.


The structure and form of extensions are defined by this document so that implementations can be created that are forward compatible with applications that might be created using singletons in the future. In addition, defining a mechanism for maintaining singletons will lend stability to this document by reducing the likely need for future revisions or updates.


Single-character subtags are assigned by IANA using the "IETF Review" policy defined by [RFC5226]. This policy requires the development of an RFC, which SHALL define the name, purpose, processes, and procedures for maintaining the subtags. The maintaining or registering authority, including name, contact email, discussion list email, and URL location of the registry, MUST be indicated clearly in the RFC. The RFC MUST specify or include each of the following:


o The specification MUST reference the specific version or revision of this document that governs its creation and MUST reference this section of this document.

o 本规范必须参考本文件的特定版本或修订版,该版本或修订版管理本规范的创建,并且必须参考本文件的本节。

o The specification and all subtags defined by the specification MUST follow the ABNF and other rules for the formation of tags and subtags as defined in this document. In particular, it MUST

o 规范和规范定义的所有子标签必须遵循ABNF和本文件中定义的标签和子标签形成的其他规则。特别是,它必须

specify that case is not significant and that subtags MUST NOT exceed eight characters in length.


o The specification MUST specify a canonical representation.

o 规范必须指定规范表示。

o The specification of valid subtags MUST be available over the Internet and at no cost.

o 有效子标签的规范必须在互联网上免费提供。

o The specification MUST be in the public domain or available via a royalty-free license acceptable to the IETF and specified in the RFC.

o 该规范必须在公共领域内,或通过IETF可接受且RFC中规定的免版税许可证提供。

o The specification MUST be versioned, and each version of the specification MUST be numbered, dated, and stable.

o 规范必须进行版本控制,规范的每个版本都必须编号、注明日期并保持稳定。

o The specification MUST be stable. That is, extension subtags, once defined by a specification, MUST NOT be retracted or change in meaning in any substantial way.

o 规格必须稳定。也就是说,一旦规范定义了扩展子标签,就不能以任何实质性的方式收回或更改其含义。

o The specification MUST include, in a separate section, the registration form reproduced in this section (below) to be used in registering the extension upon publication as an RFC.

o 本规范必须在单独一节中包含本节(下文)中复制的登记表,以便在作为RFC发布时用于登记扩展。

o IANA MUST be informed of changes to the contact information and URL for the specification.

o 必须将规范的联系信息和URL的更改通知IANA。

IANA will maintain a registry of allocated single-character (singleton) subtags. This registry MUST use the record-jar format described by the ABNF in Section 3.1.1. Upon publication of an extension as an RFC, the maintaining authority defined in the RFC MUST forward this registration form to <>, who MUST forward the request to <>. The maintaining authority of the extension MUST maintain the accuracy of the record by sending an updated full copy of the record to <> with the subject line "LANGUAGE TAG EXTENSION UPDATE" whenever content changes. Only the 'Comments', 'Contact_Email', 'Mailing_List', and 'URL' fields MAY be modified in these updates.

IANA将维护已分配单字符(单例)子标签的注册表。此注册表必须使用ABNF在第3.1.1节中描述的记录jar格式。在将扩展发布为RFC后,RFC中定义的维护机构必须将此注册表转发给<>,必须将请求转发给<>. 扩展的维护机构必须通过将更新的完整记录副本发送给<>每当内容更改时,使用主题行“语言标记扩展更新”。在这些更新中,只能修改“评论”、“联系电子邮件”、“邮件列表”和“URL”字段。

Failure to maintain this record, maintain the corresponding registry, or meet other conditions imposed by this section of this document MAY be appealed to the IESG [RFC2028] under the same rules as other IETF decisions (see [RFC2026]) and MAY result in the authority to maintain the extension being withdrawn or reassigned by the IESG.


%% Identifier: Description: Comments: Added: RFC: Authority: Contact_Email: Mailing_List: URL: %%


Figure 6: Format of Records in the Language Tag Extensions Registry

图6:Language Tag Extensions注册表中记录的格式

'Identifier' contains the single-character subtag (singleton) assigned to the extension. The Internet-Draft submitted to define the extension SHOULD specify which letter or digit to use, although the IESG MAY change the assignment when approving the RFC.


'Description' contains the name and description of the extension.


'Comments' is an OPTIONAL field and MAY contain a broader description of the extension.


'Added' contains the date the extension's RFC was published in the "full-date" format specified in [RFC3339]. For example: 2004-06-28 represents June 28, 2004, in the Gregorian calendar.


'RFC' contains the RFC number assigned to the extension.


'Authority' contains the name of the maintaining authority for the extension.


'Contact_Email' contains the email address used to contact the maintaining authority.


'Mailing_List' contains the URL or subscription email address of the mailing list used by the maintaining authority.


'URL' contains the URL of the registry for this extension.


The determination of whether an Internet-Draft meets the above conditions and the decision to grant or withhold such authority rests solely with the IESG and is subject to the normal review and appeals process associated with the RFC process.


Extension authors are strongly cautioned that many (including most well-formed) processors will be unaware of any special relationships


or meaning inherent in the order of extension subtags. Extension authors SHOULD avoid subtag relationships or canonicalization mechanisms that interfere with matching or with length restrictions that sometimes exist in common protocols where the extension is used. In particular, applications MAY truncate the subtags in doing matching or in fitting into limited lengths, so it is RECOMMENDED that the most significant information be in the most significant (left-most) subtags and that the specification gracefully handle truncated subtags.


When a language tag is to be used in a specific, known protocol, it is RECOMMENDED that the language tag not contain extensions not supported by that protocol. In addition, note that some protocols MAY impose upper limits on the length of the strings used to store or transport the language tag.


3.8. Update of the Language Subtag Registry
3.8. 更新语言子标记注册表

After the adoption of this document, the IANA Language Subtag Registry needed an update so that it would contain the complete set of subtags valid in a language tag. [RFC5645] describes the process used to create this update.


Registrations that are in process under the rules defined in [RFC4646] when this document is adopted MUST be completed under the rules contained in this document.


3.9. Applicability of the Subtag Registry
3.9. 子标签注册的适用性

The Language Subtag Registry is the source of data elements used to construct language tags, following the rules described in this document. Language tags are designed for indicating linguistic attributes of various content, including not only text but also most media formats, such as video or audio. They also form the basis for language and locale negotiation in various protocols and APIs.

Language Subtag Registry是用于构造语言标记的数据元素的源,遵循本文档中描述的规则。语言标记用于指示各种内容的语言属性,不仅包括文本,还包括大多数媒体格式,如视频或音频。它们还构成了各种协议和API中语言和区域设置协商的基础。

The registry is therefore applicable to many applications that need some form of language identification, with these limitations:


o It is not designed to be the sole data source in the creation of a language-selection user interface. For example, the registry does not contain translations for subtag descriptions or for tags composed from the subtags. Sources for localized data based on the registry are generally available, notably [CLDR]. Nor does the registry indicate which subtag combinations are particularly useful or relevant.

o 在创建语言选择用户界面时,它不是唯一的数据源。例如,注册表不包含子标签描述或子标签组成的标签的翻译。基于注册表的本地化数据源通常可用,特别是[CLDR]。注册表也没有指出哪些子标签组合特别有用或相关。

o It does not provide information indicating relationships between different languages, such as might be used in a user interface to select language tags hierarchically, regionally, or on some other organizational model.

o 它不提供指示不同语言之间关系的信息,例如可能在用户界面中用于按层次、区域或某些其他组织模型选择语言标记的信息。

o It does not supply information about potential overlap between different language tags, as the notion of what constitutes a language is not precise: several different language tags might be reasonable choices for the same given piece of content.

o 它没有提供关于不同语言标记之间潜在重叠的信息,因为构成语言的概念并不精确:对于同一给定内容,几个不同的语言标记可能是合理的选择。

o It does not contain information about appropriate fallback choices when performing language negotiation. A good fallback language might be linguistically unrelated to the specified language. The fact that one language is often used as a fallback language for another is usually a result of outside factors, such as geography, history, or culture -- factors that might not apply in all cases. For example, most people who use Breton (a Celtic language used in the Northwest of France) would probably prefer to be served French (a Romance language) if Breton isn't available.

o 它不包含有关执行语言协商时适当的回退选择的信息。一个好的后备语言可能在语言上与指定的语言无关。一种语言经常被用作另一种语言的后备语言,这一事实通常是外部因素的结果,如地理、历史或文化——这些因素可能并不适用于所有情况。例如,如果不提供Breton,大多数使用Breton(法国西北部使用的凯尔特语)的人可能更愿意使用法语(浪漫语言)。

4. Formation and Processing of Language Tags
4. 语言标记的形成与处理

This section addresses how to use the information in the registry with the tag syntax to choose, form, and process language tags.


4.1. Choice of Language Tag
4.1. 语言标记的选择

The guiding principle in forming language tags is to "tag content wisely." Sometimes there is a choice between several possible tags for the same content. The choice of which tag to use depends on the content and application in question, and some amount of judgment might be necessary when selecting a tag.


Interoperability is best served when the same language tag is used consistently to represent the same language. If an application has requirements that make the rules here inapplicable, then that application risks damaging interoperability. It is strongly RECOMMENDED that users not define their own rules for language tag choice.


Standards, protocols, and applications that reference this document normatively but apply different rules to the ones given in this section MUST specify how language tag selection varies from the guidelines given here.


To ensure consistent backward compatibility, this document contains several provisions to account for potential instability in the standards used to define the subtags that make up language tags.


These provisions mean that no valid language tag can become invalid, nor will a language tag have a narrower scope in the future (it may have a broader scope). The most appropriate language tag for a given application or content item might evolve over time, but once applied, the tag itself cannot become invalid or have its meaning wholly change.


A subtag SHOULD only be used when it adds useful distinguishing information to the tag. Extraneous subtags interfere with the meaning, understanding, and processing of language tags. In particular, users and implementations SHOULD follow the 'Prefix' and 'Suppress-Script' fields in the registry (defined in Section 3.1): these fields provide guidance on when specific additional subtags SHOULD be used or avoided in a language tag.


The choice of subtags used to form a language tag SHOULD follow these guidelines:


1. Use as precise a tag as possible, but no more specific than is justified. Avoid using subtags that are not important for distinguishing content in an application.

1. 使用尽可能精确的标记,但不要超出合理的范围。避免使用对区分应用程序中的内容不重要的子标签。

* For example, 'de' might suffice for tagging an email written in German, while "de-CH-1996" is probably unnecessarily precise for such a task.

* 例如,“de”可能足以标记用德语编写的电子邮件,而“de-CH-1996”对于此类任务可能不必要地精确。

* Note that some subtag sequences might not represent the language a casual user might expect. For example, the Swiss German (Schweizerdeutsch) language is represented by "gsw-CH" and not by "de-CH". This latter tag represents German ('de') as used in Switzerland ('CH'), also known as Swiss High German (Schweizer Hochdeutsch). Both are real languages, and distinguishing between them could be important to an application.

* 请注意,某些子标记序列可能不代表普通用户可能期望的语言。例如,瑞士德语(Schweizerdeutsch)用“gsw CH”而不是“de CH”表示。后一个标签代表瑞士使用的德语(“de”),也称为瑞士高级德语(Schweizer Hochdeutsch)。这两种语言都是真正的语言,区分它们对应用程序可能很重要。

2. The script subtag SHOULD NOT be used to form language tags unless the script adds some distinguishing information to the tag. Script subtags were first formally defined in [RFC4646]. Their use can affect matching and subtag identification for implementations of [RFC1766] or [RFC3066] (which are obsoleted by this document), as these subtags appear between the primary language and region subtags. Some applications can benefit from the use of script subtags in language tags, as long as the use is consistent for a given context. Script subtags are never appropriate for unwritten content (such as audio recordings). The field 'Suppress-Script' in the primary or extended language record in the registry indicates script subtags that do not add distinguishing information for most applications; this field

2. 脚本子标记不应用于形成语言标记,除非脚本向标记添加了一些区别信息。脚本子标签首先在[RFC4646]中正式定义。它们的使用可能会影响[RFC1766]或[RFC3066]实现的匹配和子标签标识(本文档已淘汰),因为这些子标签出现在主语言和区域子标签之间。一些应用程序可以从语言标记中使用脚本子标记中获益,只要对给定上下文的使用是一致的。脚本子标签永远不适用于未写入的内容(如录音)。注册表中主语言记录或扩展语言记录中的“抑制脚本”字段表示脚本子标签,这些子标签不为大多数应用程序添加区分信息;这个领域

defines when users SHOULD NOT include a script subtag with a particular primary language subtag.


For example, if an implementation selects content using Basic Filtering [RFC4647] (originally described in Section 14.4 of [RFC2616]) and the user requested the language range "en-US", content labeled "en-Latn-US" will not match the request and thus not be selected. Therefore, it is important to know when script subtags will customarily be used and when they ought not be used.


For example:


* The subtag 'Latn' should not be used with the primary language 'en' because nearly all English documents are written in the Latin script and it adds no distinguishing information. However, if a document were written in English mixing Latin script with another script such as Braille ('Brai'), then it might be appropriate to choose to indicate both scripts to aid in content selection, such as the application of a style sheet.

* 子标签“Latn”不应与主要语言“en”一起使用,因为几乎所有英文文档都是用拉丁语书写的,并且没有添加任何区别信息。但是,如果一个文档是用英语编写的,将拉丁语脚本与另一个脚本(如盲文(“Brai”)混合在一起,则可以选择指示这两个脚本以帮助内容选择,例如应用样式表。

* When labeling content that is unwritten (such as a recording of human speech), the script subtag should not be used, even if the language is customarily written in several scripts. Thus, the subtitles to a movie might use the tag "uz-Arab" (Uzbek, Arabic script), but the audio track for the same language would be tagged simply "uz". (The tag "uz-Zxxx" could also be used where content is not written, as the subtag 'Zxxx' represents the "Code for unwritten documents".)

* 在标记未书写的内容(如人类语音记录)时,不应使用“脚本”子标签,即使该语言通常是用多个脚本编写的。因此,电影的字幕可能会使用标签“uz-Arab”(乌兹别克语,阿拉伯语脚本),但同一种语言的音轨会被简单地标记为“uz”。(标签“uz Zxxx”也可用于未写入内容的地方,因为子标签“Zxxx”代表“未写入文件的代码”。)

3. If a tag or subtag has a 'Preferred-Value' field in its registry entry, then the value of that field SHOULD be used to form the language tag in preference to the tag or subtag in which the preferred value appears.

3. 如果标记或子标记在其注册表项中有“首选值”字段,则该字段的值应用于形成语言标记,优先于首选值出现的标记或子标记。

* For example, use 'jbo' for Lojban in preference to the grandfathered tag "art-lojban".

* 例如,在Lojban中使用'jbo'优先于祖父标记“art Lojban”。

4. Use subtags or sequences of subtags for individual languages in preference to subtags for language collections. A "language collection" is a group of languages that are descended from a common ancestor, are spoken in the same geographical area, or are otherwise related. Certain language collections are assigned codes by [ISO639-5] (and some of these [ISO639-5] codes are also defined as collections in [ISO639-2]). These codes are included as primary language subtags in the registry. Subtags for a language collection in the registry have a 'Scope' field with a value of 'collection'. A subtag for a language collection is

4. 与使用语言集合的子标记相比,使用单个语言的子标记或子标记序列更可取。“语言集合”是一组语言,这些语言是从一个共同的祖先传下来的,在同一个地理区域内使用,或以其他方式相关。某些语言集合由[ISO639-5]指定代码(其中一些[ISO639-5]代码在[ISO639-2]中也定义为集合)。这些代码作为主语言子标签包含在注册表中。注册表中语言集合的子标记有一个值为“collection”的“Scope”字段。语言集合的子标记为

always preferred to less specific alternatives such as 'mul' and 'und' (see below), and a subtag representing a language collection MAY be used when more specific language information is not available. However, most users and implementations do not know there is a relationship between the collection and its individual languages. In addition, the relationship between the individual languages in the collection is not well defined; in particular, the languages are usually not mutually intelligible. Since the subtags are different, a request for the collection will typically only produce items tagged with the collection's subtag, not items tagged with subtags for the individual languages contained in the collection.


* For example, collections are interpreted inclusively, so the subtag 'gem' (Germanic languages) could, but SHOULD NOT, be used with content that would be better tagged with "en" (English), "de" (German), or "gsw" (Swiss German, Alemannic). While 'gem' collects all of these (and other) languages, most implementations will not match 'gem' to the individual languages; thus, using the subtag will not produce the desired result.

* 例如,集合的解释是包容性的,因此子标签“gem”(日耳曼语)可以(但不应该)与标记为“en”(英语)、“de”(德语)或“gsw”(瑞士德语、阿勒曼语)的内容一起使用。虽然“gem”收集所有这些(和其他)语言,但大多数实现不会将“gem”与单个语言相匹配;因此,使用子标签不会产生期望的结果。

5. [ISO639-2] has defined several codes included in the subtag registry that require additional care when choosing language tags. In most of these cases, where omitting the language tag is permitted, such omission is preferable to using these codes. Language tags SHOULD NOT incorporate these subtags as a prefix, unless the additional information conveys some value to the application.

5. [ISO639-2]定义了子标记注册表中包含的几个代码,这些代码在选择语言标记时需要额外小心。在大多数情况下,如果允许省略语言标记,则这种省略比使用这些代码更可取。语言标记不应将这些子标记作为前缀合并,除非附加信息向应用程序传递了一些值。

* The 'mul' (Multiple) primary language subtag identifies content in multiple languages. This subtag SHOULD NOT be used when a list of languages or individual tags for each content element can be used instead. For example, the 'Content-Language' header [RFC3282] allows a list of languages to be used, not just a single language tag.

* “mul”(多)主语言子标签标识多语言的内容。当可以使用语言列表或每个内容元素的单个标记时,不应使用此子标记。例如,“内容语言”标题[RFC3282]允许使用语言列表,而不仅仅是单个语言标记。

* The 'und' (Undetermined) primary language subtag identifies linguistic content whose language is not determined. This subtag SHOULD NOT be used unless a language tag is required and language information is not available or cannot be determined. Omitting the language tag (where permitted) is preferred. The 'und' subtag might be useful for protocols that require a language tag to be provided or where a primary language subtag is required (such as in "und-Latn"). The 'und' subtag MAY also be useful when matching language tags in certain situations.

* “und”(待定)主语言子标签标识语言未确定的语言内容。除非需要语言标记且语言信息不可用或无法确定,否则不应使用此子标记。最好省略语言标记(如果允许)。“und”子标记对于需要提供语言标记的协议或需要主语言子标记的协议(例如在“und-Latn”中)可能很有用。在某些情况下,当匹配语言标记时,“und”子标记可能也很有用。

* The 'zxx' (Non-Linguistic, Not Applicable) primary language subtag identifies content for which a language classification is inappropriate or does not apply. Some examples might include instrumental or electronic music; sound recordings consisting of nonverbal sounds; audiovisual materials with no narration, dialog, printed titles, or subtitles; machine-readable data files consisting of machine languages or character codes; or programming source code.

* “zxx”(非语言,不适用)主语言子标签标识语言分类不合适或不适用的内容。一些例子可能包括器乐或电子音乐;由非语言声音组成的录音;没有旁白、对话、印刷标题或字幕的视听材料;由机器语言或字符代码组成的机器可读数据文件;或编写源代码。

* The 'mis' (Uncoded) primary language subtag identifies content whose language is known but that does not currently have a corresponding subtag. This subtag SHOULD NOT be used. Because the addition of other codes in the future can render its application invalid, it is inherently unstable and hence incompatible with the stability goals of BCP 47. It is always preferable to use other subtags: either 'und' or (with prior agreement) private use subtags.

* “mis”(未编码)主语言子标签标识语言已知但当前没有相应子标签的内容。不应使用此子标签。由于将来添加其他代码可能导致其应用程序无效,因此它本身不稳定,因此与BCP 47的稳定性目标不兼容。最好使用其他子标签:“und”或(事先同意)私用子标签。

6. Use variant subtags sparingly and in the correct order. Most variant subtags have one or more 'Prefix' fields in the registry that express the list of subtags with which they are appropriate. Variants SHOULD only be used with subtags that appear in one of these 'Prefix' fields. If a variant lists a second variant in one of its 'Prefix' fields, the first variant SHOULD appear directly after the second variant in any language tag where both occur. General purpose variants (those with no 'Prefix' fields at all) SHOULD appear after any other variant subtags. Order any remaining variants by placing the most significant subtag first. If none of the subtags is more significant or no relationship can be determined, alphabetize the subtags. Because variants are very specialized, using many of them together generally makes the tag so narrow as to override the additional precision gained. Putting the subtags into another order interferes with interoperability, as well as the overall interpretation of the tag.

6. 以正确的顺序谨慎使用变体子标签。大多数变体子标签在注册表中都有一个或多个“前缀”字段,用于表示相应的子标签列表。变体只能与出现在其中一个“前缀”字段中的子标记一起使用。如果一个变体在其“前缀”字段中列出了第二个变体,则第一个变体应直接出现在第二个变体之后的任何语言标记中,其中两个变体都出现。通用变量(完全没有“前缀”字段的变量)应出现在任何其他变量子标签之后。通过将最重要的子标签放在第一位来订购任何剩余的变体。如果没有任何子标签更重要或无法确定关系,请按字母顺序排列子标签。因为变体是非常专门化的,将它们中的许多一起使用通常会使标记非常窄,从而覆盖获得的额外精度。将子标签放入另一个顺序会干扰互操作性以及标签的整体解释。

For example:


* The tag "en-scotland-fonipa" (English, Scottish dialect, IPA phonetic transcription) is correctly ordered because 'scotland' has a 'Prefix' of "en", while 'fonipa' has no 'Prefix' field.

* 标记“en scotland fonipa”(英语、苏格兰方言、IPA拼音)的顺序正确,因为“scotland”的“前缀”为“en”,而“fonipa”没有“前缀”字段。

* The tag "sl-IT-rozaj-biske-1994" is correctly ordered: 'rozaj' lists "sl" as its sole 'Prefix'; 'biske' lists "sl-rozaj" as its sole 'Prefix'. The subtag '1994' has several prefixes,

* 标签“sl-IT-rozaj-biske-1994”的顺序正确:“rozaj”将“sl”列为其唯一的“前缀”biske'将“sl rozaj”列为其唯一的“前缀”。子标签“1994”有几个前缀,

including "sl-rozaj". However, it follows both 'rozaj' and 'biske' because one of its 'Prefix' fields is "sl-rozaj-biske".

包括“sl rozaj”。但是,它紧跟在“rozaj”和“biske”之后,因为它的一个“前缀”字段是“sl rozaj biske”。

7. The grandfathered tag "i-default" (Default Language) was originally registered according to [RFC1766] to meet the needs of [RFC2277]. It is not used to indicate a specific language, but rather to identify the condition or content used where the language preferences of the user cannot be established. It SHOULD NOT be used except as a means of labeling the default content for applications or protocols that require default language content to be labeled with that specific tag. It MAY also be used by an application or protocol to identify when the default language content is being returned.

7. 祖父标记“i-default”(默认语言)最初是根据[RFC1766]注册的,以满足[RFC2277]的需要。它不用于指示特定的语言,而是用于识别无法建立用户语言首选项时使用的条件或内容。对于需要使用特定标记标记默认语言内容的应用程序或协议,不应将其用作标记默认内容的方法。应用程序或协议也可以使用它来标识何时返回默认语言内容。

4.1.1. Tagging Encompassed Languages
4.1.1. 标记包含的语言

Some primary language records in the registry have a 'Macrolanguage' field (Section 3.1.10) that contains a mapping from each "encompassed language" to its macrolanguage. The 'Macrolanguage' mapping doesn't define what the relationship between the encompassed language and its macrolanguage is, nor does it define how languages encompassed by the same macrolanguage are related to each other. Two different languages encompassed by the same macrolanguage may differ from one another more than, say, French and Spanish do.


A few specific macrolanguages, such as Chinese ('zh') and Arabic ('ar'), are handled differently. See Section 4.1.2.


The more specific encompassed language subtag SHOULD be used to form the language tag, although either the macrolanguage's primary language subtag or the encompassed language's subtag MAY be used. This means, for example, tagging Plains Cree with 'crk' rather than 'cr' (Cree), and so forth.

虽然可以使用宏语言的主语言子标记或包含语言的子标记,但应使用更具体的包含语言子标记来形成语言标记。这意味着,例如,用“crk”而不是“cr”(Cree)标记Plains Cree,等等。

Each macrolanguage subtag's scope, by definition, includes all of its encompassed languages. Since the relationship between encompassed languages varies, users cannot assume that the macrolanguage subtag means any particular encompassed language, nor that any given pair of encompassed languages are mutually intelligible or otherwise interchangeable.


Applications MAY use macrolanguage information to improve matching or language negotiation. For example, the information that 'sr' (Serbian) and 'hr' (Croatian) share a macrolanguage expresses a closer relation between those languages than between, say, 'sr' (Serbian) and 'ma' (Macedonian). However, this relationship is not guaranteed nor is it exclusive. For example, Romanian ('ro') and


Moldavian ('mo') do not share a macrolanguage, but are far more closely related to each other than Cantonese ('yue') and Wu ('wuu'), which do share a macrolanguage.


4.1.2. Using Extended Language Subtags
4.1.2. 使用扩展语言子标签

To accommodate language tag forms used prior to the adoption of this document, language tags provide a special compatibility mechanism: the extended language subtag. Selected languages have been provided with both primary and extended language subtags. These include macrolanguages, such as Malay ('ms') and Uzbek ('uz'), that have a specific dominant variety that is generally synonymous with the macrolanguage. Other languages, such as the Chinese ('zh') and Arabic ('ar') macrolanguages and the various sign languages ('sgn'), have traditionally used their primary language subtag, possibly coupled with various region subtags or as part of a registered grandfathered tag, to indicate the language.


With the adoption of this document, specific ISO 639-3 subtags became available to identify the languages contained within these diverse language families or groupings. This presents a choice of language tags where previously none existed:

随着本文件的采用,特定的ISO 639-3子标签可用于识别这些不同语系或分组中包含的语言。这提供了以前不存在的语言标记的选择:

o Each encompassed language's subtag SHOULD be used as the primary language subtag. For example, a document in Mandarin Chinese would be tagged "cmn" (the subtag for Mandarin Chinese) in preference to "zh" (Chinese).

o 每个包含语言的子标签都应该用作主语言子标签。例如,中文文档将标记为“cmn”(中文的子标签),而不是“zh”(中文)。

o If compatibility is desired or needed, the encompassed subtag MAY be used as an extended language subtag. For example, a document in Mandarin Chinese could be tagged "zh-cmn" instead of either "cmn" or "zh".

o 如果希望或需要兼容性,则包含的子标记可以用作扩展语言子标记。例如,中文文档可以标记为“zh-cmn”,而不是“cmn”或“zh”。

o The macrolanguage or prefixing subtag MAY still be used to form the tag instead of the more specific encompassed language subtag. That is, tags such as "zh-HK" or "sgn-RU" are still valid.

o 宏语言或前缀子标记仍然可以用于形成标记,而不是更具体的包含语言子标记。也就是说,诸如“zh HK”或“sgn RU”之类的标记仍然有效。

Chinese ('zh') provides a useful illustration of this. In the past, various content has used tags beginning with the 'zh' subtag, with application-specific meaning being associated with region codes, private use sequences, or grandfathered registered values. This is because historically only the macrolanguage subtag 'zh' was available for forming language tags. However, the languages encompassed by the Chinese subtag 'zh' are, in the main, not mutually intelligible when spoken, and the written forms of these languages also show wide variation in form and usage.


To provide compatibility, Chinese languages encompassed by the 'zh' subtag are in the registry both as primary language subtags and as extended language subtags. For example, the ISO 639-3 code for Cantonese is 'yue'. Content in Cantonese might historically have used a tag such as "zh-HK" (since Cantonese is commonly spoken in Hong Kong), although that tag actually means any type of Chinese as used in Hong Kong. With the availability of ISO 639-3 codes in the registry, content in Cantonese can be directly tagged using the 'yue' subtag. The content can use it as a primary language subtag, as in the tag "yue-HK" (Cantonese, Hong Kong). Or it can use an extended language subtag with 'zh', as in the tag "zh-yue-Hant" (Chinese, Cantonese, Traditional script).

为了提供兼容性,“zh”子标签包含的中文作为主语言子标签和扩展语言子标签在注册表中。例如,粤语的ISO 639-3代码为“粤语”。广东话的内容可能在历史上使用了“ZH-HK”这样的标签(因为广东话在香港是通用的),尽管这个标签实际上是香港使用的任何中文类型。注册中心提供ISO 639-3代码后,可以使用“粤语”子标签直接标记粤语内容。内容可以将其用作主要语言子标签,如标签“yue HK”(粤语,香港)。或者它可以使用带有“zh”的扩展语言子标签,如标签“zh yue Hant”(中文、广东话、繁体字)。

As noted above, applications can choose to use the macrolanguage subtag to form the tag instead of using the more specific encompassed language subtag. For example, an application with large quantities of data already using tags with the 'zh' (Chinese) subtag might continue to use this more general subtag even for new data, even though the content could be more precisely tagged with 'cmn' (Mandarin), 'yue' (Cantonese), 'wuu' (Wu), and so on. Similarly, an application already using tags that start with the 'ar' (Arabic) subtag might continue to use this more general subtag even for new data, which could be more precisely tagged with 'arb' (Standard Arabic).


In some cases, the encompassed languages had tags registered for them during the RFC 3066 era. Those grandfathered tags not already deprecated or rendered redundant were deprecated in the registry upon adoption of this document. As grandfathered values, they remain valid for use, and some content or applications might use them. As with other grandfathered tags, since implementations might not be able to associate the grandfathered tags with the encompassed language subtag equivalents that are recommended by this document, implementations are encouraged to canonicalize tags for comparison purposes. Some examples of this include the tags "zh-hakka" (Hakka) and "zh-guoyu" (Mandarin or Standard Chinese).


Sign languages share a mode of communication rather than a linguistic heritage. There are many sign languages that have developed independently, and the subtag 'sgn' indicates only the presence of a sign language. A number of sign languages also had grandfathered tags registered for them during the RFC 3066 era. For example, the grandfathered tag "sgn-US" was registered to represent 'American Sign Language' specifically, without reference to the United States. This is still valid, but deprecated: a document in American Sign Language can be labeled either "ase" or "sgn-ase" (the 'ase' subtag is for the language called 'American Sign Language').

手语共享一种交流方式,而不是语言遗产。有许多手语是独立开发的,子标签“sgn”仅表示手语的存在。在RFC3066时代,许多手语也为它们注册了祖父标记。例如,祖父标记“sgn US”被注册为专门代表“美国手语”,没有提及美国。这仍然有效,但已弃用:美国手语的文档可以标记为“ase”或“sgn ase”(“ase”子标记用于称为“美国手语”的语言)。

4.2. Meaning of the Language Tag
4.2. 语言标记的意义

The meaning of a language tag is related to the meaning of the subtags that it contains. Each subtag, in turn, implies a certain range of expectations one might have for related content, although it is not a guarantee. For example, the use of a script subtag such as 'Arab' (Arabic script) does not mean that the content contains only Arabic characters. It does mean that the language involved is predominantly in the Arabic script. Thus, a language tag and its subtags can encompass a very wide range of variation and yet remain appropriate in each particular instance.


Validity of a tag is not the only factor determining its usefulness. While every valid tag has a meaning, it might not represent any real-world language usage. This is unavoidable in a system in which subtags can be combined freely. For example, tags such as "ar-Cyrl-CO" (Arabic, Cyrillic script, as used in Colombia) or "tlh-Kore-AQ-fonipa" (Klingon, Korean script, as used in Antarctica, IPA phonetic transcription) are both valid and unlikely to represent a useful combination of language attributes.

标签的有效性并不是决定其有用性的唯一因素。虽然每个有效标记都有一个含义,但它可能并不代表任何实际的语言用法。在子标签可以自由组合的系统中,这是不可避免的。例如,“ar Cyrl CO”(阿拉伯语,西里尔文,如哥伦比亚所用)或“tlh Kore AQ fonipa”(克林贡语,韩语,如南极洲所用,如IPA拼音)等标记既有效,也不可能代表语言属性的有用组合。

The meaning of a given tag doesn't depend on the context in which it appears. The relationship between a tag's meaning and the information objects to which that tag is applied, however, can vary.


o For a single information object, the associated language tags might be interpreted as the set of languages that is necessary for a complete comprehension of the complete object. Example: Plain text documents.

o 对于单个信息对象,关联的语言标记可能被解释为完整理解完整对象所必需的一组语言。示例:纯文本文档。

o For an aggregation of information objects, the associated language tags could be taken as the set of languages used inside components of that aggregation. Examples: Document stores and libraries.

o 对于信息对象的聚合,关联的语言标记可以作为该聚合组件内部使用的语言集。示例:文档存储和库。

o For information objects whose purpose is to provide alternatives, the associated language tags could be regarded as a hint that the content is provided in several languages and that one has to inspect each of the alternatives in order to find its language or languages. In this case, the presence of multiple tags might not mean that one needs to be multilingual to get complete understanding of the document. Example: MIME multipart/ alternative [RFC2046].

o 对于其目的是提供备选方案的信息对象,相关的语言标记可以被视为一种提示,表明内容是以几种语言提供的,并且必须检查每种备选方案才能找到其语言。在这种情况下,多个标记的存在可能并不意味着需要使用多种语言才能完全理解文档。示例:MIME多部分/alternative[RFC2046]。

o For markup languages, such as HTML and XML, language information can be added to each part of the document identified by the markup structure (including the whole document itself). For example, one could write <span lang="fr">C'est la vie.</span> inside a German document; the German-speaking user could then access a French-

o 对于HTML和XML等标记语言,可以将语言信息添加到由标记结构标识的文档的每个部分(包括整个文档本身)。例如,一个人可以在一份德语文档中写下“生活就是这样”</span>;说德语的用户可以访问法语-

German dictionary to find out what the marked section meant. If the user were listening to that document through a speech synthesis interface, this formation could be used to signal the synthesizer to appropriately apply French text-to-speech pronunciation rules to that span of text, instead of applying the inappropriate German rules.


o For markup languages and document formats that allow the audience to be identified, a language tag could indicate the audience(s) appropriate for that document. For example, the same HTML document described in the preceding bullet might have an HTTP header "Content-Language: de" to indicate that the intended audience for the file is German (even though three words appear and are identified as being in French within it).

o 对于允许识别访问者的标记语言和文档格式,语言标记可以指示适合该文档的访问者。例如,前面项目符号中描述的同一个HTML文档可能有一个HTTP头“Content Language:de”,以指示该文件的目标读者是德语(即使其中出现了三个单词,并且被标识为法语)。

o For systems and APIs, language tags form the basis for most implementations of locale identifiers. For example, see Unicode's CLDR (Common Locale Data Repository) (see UTS #35 [UTS35]) project.

o 对于系统和API,语言标记构成了大多数区域设置标识符实现的基础。例如,请参见Unicode的CLDR(公共语言环境数据存储库)(请参见UTS#35[UTS35])项目。

Language tags are related when they contain a similar sequence of subtags. For example, if a language tag B contains language tag A as a prefix, then B is typically "narrower" or "more specific" than A. Thus, "zh-Hant-TW" is more specific than "zh-Hant".

当语言标记包含相似的子标记序列时,它们是相关的。例如,如果语言标记B包含语言标记a作为前缀,则B通常比a“更窄”或“更具体”。因此,“zh Hant TW”比“zh Hant”更具体。

This relationship is not guaranteed in all cases: specifically, languages that begin with the same sequence of subtags are NOT guaranteed to be mutually intelligible, although they might be. For example, the tag "az" shares a prefix with both "az-Latn" (Azerbaijani written using the Latin script) and "az-Cyrl" (Azerbaijani written using the Cyrillic script). A person fluent in one script might not be able to read the other, even though the linguistic content (e.g., what would be heard if both texts were read aloud) might be identical. Content tagged as "az" most probably is written in just one script and thus might not be intelligible to a reader familiar with the other script.


Similarly, not all subtags specify an actual distinction in language. For example, the tags "en-US" and "en-CA" mean, roughly, English with features generally thought to be characteristic of the United States and Canada, respectively. They do not imply that a significant dialectical boundary exists between any arbitrarily selected point in the United States and any arbitrarily selected point in Canada. Neither does a particular region subtag imply that linguistic distinctions do not exist within that region.

类似地,并非所有子标签都指定语言中的实际区别。例如,标签“en US”和“en CA”粗略地表示英语,其特征通常被认为分别是美国和加拿大的特征。它们并不意味着在美国任意选择的点和加拿大任意选择的点之间存在着明显的辩证界限。特定的区域子标签也不意味着该区域内不存在语言差异。

4.3. Lists of Languages
4.3. 语言清单

In some applications, a single content item might best be associated with more than one language tag. Examples of such a usage include:


o Content items that contain multiple, distinct varieties. Often this is used to indicate an appropriate audience for a given content item when multiple choices might be appropriate. Examples of this could include:

o 包含多个不同变体的内容项。通常,当可能需要多选时,这用于表示给定内容项的适当受众。这方面的例子包括:

* Metadata about the appropriate audience for a movie title. For example, a DVD might label its individual audio tracks 'de' (German), 'fr' (French), and 'es' (Spanish), but the overall title would list "de, fr, es" as its overall audience.

* 关于电影标题的适当观众的元数据。例如,DVD可能会将其单独的音轨标记为“de”(德语)、“fr”(法语)和“es”(西班牙语),但总体标题会将“de、fr、es”列为其总体观众。

* A French/English, English/French dictionary tagged as both "en" and "fr" to specify that it applies equally to French and English.

* 法语/英语、英语/法语词典,标注为“en”和“fr”,以说明其同样适用于法语和英语。

* A side-by-side or interlinear translation of a document, as is commonly done with classical works in Latin or Greek.

* 并排翻译一份文件的并排或行间翻译,常用于拉丁语或希腊语的古典作品。

o Content items that contain a single language but that require multiple levels of specificity. For example, a library might wish to classify a particular work as both Norwegian ('no') and as Nynorsk ('nn') for audiences capable of appreciating the distinction or needing to select content more narrowly.

o 包含单一语言但需要多个特定级别的内容项。例如,图书馆可能希望将特定作品同时归类为挪威语(“no”)和尼诺尔斯克语(“nn”),以便读者能够欣赏其区别或需要更狭隘地选择内容。

4.4. Length Considerations
4.4. 长度考虑

There is no defined upper limit on the size of language tags. While historically most language tags have consisted of language and region subtags with a combined total length of up to six characters, larger tags have always been both possible and have actually appeared in use.


Neither the language tag syntax nor other requirements in this document impose a fixed upper limit on the number of subtags in a language tag (and thus an upper bound on the size of a tag). The language tag syntax suggests that, depending on the specific language, more subtags (and thus a longer tag) are sometimes necessary to completely identify the language for certain applications; thus, it is possible to envision long or complex subtag sequences.


4.4.1. Working with Limited Buffer Sizes
4.4.1. 使用有限的缓冲区大小

Some applications and protocols are forced to allocate fixed buffer sizes or otherwise limit the length of a language tag. A conformant implementation or specification MAY refuse to support the storage of language tags that exceed a specified length. Any such limitation SHOULD be clearly documented, and such documentation SHOULD include what happens to longer tags (for example, whether an error value is generated or the language tag is truncated). A protocol that allows tags to be truncated at an arbitrary limit, without giving any indication of what that limit is, has the potential to cause harm by changing the meaning of tags in substantial ways.


In practice, most language tags do not require more than a few subtags and will not approach reasonably sized buffer limitations; see Section 4.1.


Some specifications or protocols have limits on tag length but do not have a fixed length limitation. For example, [RFC2231] has no explicit length limitation: the length available for the language tag is constrained by the length of other header components (such as the charset's name) coupled with the 76-character limit in [RFC2047]. Thus, the "limit" might be 50 or more characters, but it could potentially be quite small.


The considerations for assigning a buffer limit are:


Implementations SHOULD NOT truncate language tags unless the meaning of the tag is purposefully being changed, or unless the tag does not fit into a limited buffer size specified by a protocol for storage or transmission.


Implementations SHOULD warn the user when a tag is truncated since truncation changes the semantic meaning of the tag.


Implementations of protocols or specifications that are space constrained but do not have a fixed limit SHOULD use the longest possible tag in preference to truncation.


Protocols or specifications that specify limited buffer sizes for language tags MUST allow for language tags of at least 35 characters. Note that [RFC4646] recommended a minimum field size of 42 characters because it included all three elements of the 'extlang' production. Two of these are now permanently reserved, so a registered primary language subtag of the maximum length of 8 characters is now longer than the longest language-extlang combination. Protocols or specifications that commonly use


extensions or private use subtags might wish to reserve or recommend a longer "minimum buffer" size.


The following illustration shows how the 35-character recommendation was derived:


   language      =  8 ; longest allowed registered value
                      ;   longer than primary+extlang
                      ;   which requires 7 characters
   script        =  5 ; if not suppressed: see Section 4.1
   region        =  4 ; UN M.49 numeric region code
                      ;   ISO 3166-1 codes require 3
   variant1      =  9 ; needs 'language' as a prefix
   variant2      =  9 ; very rare, as it needs
                      ;   'language-variant1' as a prefix
   language      =  8 ; longest allowed registered value
                      ;   longer than primary+extlang
                      ;   which requires 7 characters
   script        =  5 ; if not suppressed: see Section 4.1
   region        =  4 ; UN M.49 numeric region code
                      ;   ISO 3166-1 codes require 3
   variant1      =  9 ; needs 'language' as a prefix
   variant2      =  9 ; very rare, as it needs
                      ;   'language-variant1' as a prefix
   total         = 35 characters
   total         = 35 characters

Figure 7: Derivation of the Limit on Tag Length


4.4.2. Truncation of Language Tags
4.4.2. 语言标记的截断

Truncation of a language tag alters the meaning of the tag, and thus SHOULD be avoided. However, truncation of language tags is sometimes necessary due to limited buffer sizes. Such truncation MUST NOT permit a subtag to be chopped off in the middle or the formation of invalid tags (for example, one ending with the "-" character).


This means that applications or protocols that truncate tags MUST do so by progressively removing subtags along with their preceding "-" from the right side of the language tag until the tag is short enough for the given buffer. If the resulting tag ends with a single-character subtag, that subtag and its preceding "-" MUST also be removed. For example:


Tag to truncate: zh-Latn-CN-variant1-a-extend1-x-wadegile-private1 1. zh-Latn-CN-variant1-a-extend1-x-wadegile 2. zh-Latn-CN-variant1-a-extend1 3. zh-Latn-CN-variant1 4. zh-Latn-CN 5. zh-Latn 6. zh

要截断的标记:zh-Latn-CN-variant1-a-extend1-x-wadegile-private1。zh-Latn-CN-variant1-a-extend1-x-wadegile 2。zh-Latn-CN-variant1-a-EXTEND13。zh-Latn-CN-variant1 4。zh Latn CN 5。zh Latn 6。zh

Figure 8: Example of Tag Truncation


4.5. Canonicalization of Language Tags
4.5. 语言标记的规范化

Since a particular language tag can be used by many processes, language tags SHOULD always be created or generated in canonical form.


A language tag is in 'canonical form' when the tag is well-formed according to the rules in Sections 2.1 and 2.2 and it has been canonicalized by applying each of the following steps in order, using data from the IANA registry (see Section 3.1):


1. Extension sequences are ordered into case-insensitive ASCII order by singleton subtag.

1. 扩展序列由singleton子标记按不区分大小写的ASCII顺序排序。

* For example, the subtag sequence '-a-babble' comes before '-b-warble'.

* 例如,子标记序列'-a-babble'位于'-b-warble'之前。

2. Redundant or grandfathered tags are replaced by their 'Preferred-Value', if there is one.

2. 如果存在“首选值”,则冗余或冗余标记将替换为它们的“首选值”。

* The field-body of the 'Preferred-Value' for grandfathered and redundant tags is an "extended language range" [RFC4647] and might consist of more than one subtag.

* grandfathered和冗余标记的“首选值”字段体是“扩展语言范围”[RFC4647],可能包含多个子标记。

* 'Preferred-Value' fields in the registry provide mappings from deprecated tags to modern equivalents. Many of these were created before the adoption of this document (such as the mapping of "no-nyn" to "nn" or "i-klingon" to "tlh"). Others are the result of later registrations or additions to the registry as permitted or required by this document (for example, "zh-hakka" was deprecated in favor of the ISO 639-3 code 'hak' when this document was adopted).

* 注册表中的“首选值”字段提供从不推荐的标记到现代等效标记的映射。其中许多都是在本文件通过之前创建的(如“no nyn”到“nn”或“i-klingon”到“tlh”的映射)。其他原因是本文件允许或要求的后续注册或注册增加的结果(例如,当采用本文件时,“zh hakka”被弃用,取而代之的是ISO 639-3代码“hak”)。

3. Subtags are replaced by their 'Preferred-Value', if there is one. For extlangs, the original primary language subtag is also replaced if there is a primary language subtag in the 'Preferred-Value'.

3. 如果存在子标记,则子标记将替换为其“首选值”。对于extlangs,如果“首选值”中有主语言子标记,则也会替换原始主语言子标记。

* The field-body of the 'Preferred-Value' for extlangs is an "extended language range" and typically maps to a primary language subtag. For example, the subtag sequence "zh-hak" (Chinese, Hakka) is replaced with the subtag 'hak' (Hakka).

* extlangs的“首选值”字段体是“扩展语言范围”,通常映射到主语言子标记。例如,子标签序列“zh hak”(中文,客家语)被替换为子标签“hak”(客家语)。

* Most of the non-extlang subtags are either Region subtags where the country name or designation has changed or clerical corrections to ISO 639-1.

* 大多数非extlang子标签都是国家名称或名称已更改的地区子标签,或者是ISO 639-1的文书更正。

The canonical form contains no 'extlang' subtags. There is an alternate 'extlang form' that maintains or reinstates extlang subtags. This form can be useful in environments where the presence of the 'Prefix' subtag is considered beneficial in matching or selection (see Section 4.1.2).


A language tag is in 'extlang form' when the tag is well-formed according to the rules in Sections 2.1 and 2.2 and it has been processed by applying each of the following two steps in order, using data from the IANA registry:

当标记根据第2.1节和第2.2节中的规则格式良好,并且已使用IANA注册表中的数据按顺序应用以下两个步骤进行处理时,语言标记为“extlang form”:

1. The language tag is first transformed into canonical form, as described above.

1. 如上所述,首先将语言标记转换为规范形式。

2. If the language tag starts with a primary language subtag that is also an extlang subtag, then the language tag is prepended with the extlang's 'Prefix'.

2. 如果language标记以同时也是extlang子标记的primary language子标记开头,则language标记前面会加上extlang的“前缀”。

* For example, "hak-CN" (Hakka, China) has the primary language subtag 'hak', which in turn has an 'extlang' record with a 'Prefix' 'zh' (Chinese). The extlang form is "zh-hak-CN" (Chinese, Hakka, China).

* 例如,“hak CN”(中国客家语)有一个主语言子标签“hak”,而该子标签又有一个带有“前缀”“zh”(中文)的“extlang”记录。extlang形式是“zh hak CN”(中文,客家语,中国)。

* Note that Step 2 (prepending a prefix) can restore a subtag that was removed by Step 1 (canonicalizing).

* 请注意,步骤2(前缀的前置)可以恢复步骤1(规范化)删除的子标记。

Example: The language tag "en-a-aaa-b-ccc-bbb-x-xyz" is in canonical form, while "en-b-ccc-bbb-a-aaa-X-xyz" is well-formed and potentially valid (extensions 'a' and 'b' are not defined as of the publication of this document) but not in canonical form (the extensions are not in alphabetical order).


Example: Although the tag "en-BU" (English as used in Burma) maintains its validity, the language tag "en-BU" is not in canonical form because the 'BU' subtag has a canonical mapping to 'MM' (Myanmar).


Canonicalization of language tags does not imply anything about the use of upper- or lowercase letters when processing or comparing subtags (and as described in Section 2.1). All comparisons MUST be performed in a case-insensitive manner.


When performing canonicalization of language tags, processors MAY regularize the case of the subtags (that is, this process is OPTIONAL), following the case used in the registry (see Section 2.1.1).


If more than one variant appears within a tag, processors MAY reorder the variants to obtain better matching behavior or more consistent presentation. Reordering of the variants SHOULD follow the recommendations for variant ordering in Section 4.1.


If the field 'Deprecated' appears in a registry record without an accompanying 'Preferred-Value' field, then that tag or subtag is deprecated without a replacement. These values are canonical when they appear in a language tag. However, tags that include these values SHOULD NOT be selected by users or generated by implementations.


An extension MUST define any relationships that exist between the various subtags in the extension and thus MAY define an alternate canonicalization scheme for the extension's subtags. Extensions MAY define how the order of the extension's subtags is interpreted. For example, an extension could define that its subtags are in canonical order when the subtags are placed into ASCII order: that is, "en-a-aaa-bbb-ccc" instead of "en-a-ccc-bbb-aaa". Another extension might define that the order of the subtags influences their semantic meaning (so that "en-b-ccc-bbb-aaa" has a different value from "en-b-aaa-bbb-ccc"). However, extension specifications SHOULD be designed so that they are tolerant of the typical processes described in Section 3.7.


4.6. Considerations for Private Use Subtags
4.6. 专用子标签的注意事项

Private use subtags, like all other subtags, MUST conform to the format and content constraints in the ABNF. Private use subtags have no meaning outside the private agreement between the parties that intend to use or exchange language tags that employ them. The same subtags MAY be used with a different meaning under a separate private agreement. They SHOULD NOT be used where alternatives exist and SHOULD NOT be used in content or protocols intended for general use.


Private use subtags are simply useless for information exchange without prior arrangement. The value and semantic meaning of private use tags and of the subtags used within such a language tag are not defined by this document.


Private use sequences introduced by the 'x' singleton are completely opaque to users or implementations outside of the private use agreement. So, in addition to private use subtag sequences introduced by the singleton subtag 'x', the Language Subtag Registry provides private use language, script, and region subtags derived from the private use codes assigned by the underlying standards. These subtags are valid for use in forming language tags; they are RECOMMENDED over the 'x' singleton private use subtag sequences


because they convey more information via their linkage to the language tag's inherent structure.


For example, the region subtags 'AA', 'ZZ', and those in the ranges 'QM'-'QZ' and 'XA'-'XZ' (derived from the ISO 3166-1 private use codes) can be used to form a language tag. A tag such as "zh-Hans-XQ" conveys a great deal of public, interchangeable information about the language material (that it is Chinese in the simplified Chinese script and is suitable for some geographic region 'XQ'). While the precise geographic region is not known outside of private agreement, the tag conveys far more information than an opaque tag such as "x-somelang" or even "zh-Hans-x-xq" (where the 'xq' subtag's meaning is entirely opaque).

例如,区域子标签“AA”、“ZZ”以及范围“QM”-“QZ”和“XA”-“XZ”(源自ISO 3166-1专用代码)中的子标签可用于形成语言标签。像“zh Hans XQ”这样的标签传达了大量关于语言材料的公开、可互换的信息(即它是简体中文,适合某些地理区域的“XQ”)。虽然在私人协议之外不知道确切的地理区域,但标签所传达的信息远远多于不透明标签,如“x-somelang”甚至“zh-Hans-x-xq”(其中“xq”子标签的含义完全不透明)。

However, in some cases content tagged with private use subtags can interact with other systems in a different and possibly unsuitable manner compared to tags that use opaque, privately defined subtags, so the choice of the best approach sometimes depends on the particular domain in question.


5. IANA Considerations
5. IANA考虑

This section deals with the processes and requirements necessary for IANA to maintain the subtag and extension registries as defined by this document and in accordance with the requirements of [RFC5226].


The impact on the IANA maintainers of the two registries defined by this document will be a small increase in the frequency of new entries or updates. IANA also is required to create a new mailing list (described below in Section 5.1) to announce registry changes and updates.


5.1. Language Subtag Registry
5.1. 语言子标记注册表

IANA updated the registry using instructions and content provided in a companion document [RFC5645]. The criteria and process for selecting the updated set of records are described in that document. The updated set of records represents no impact on IANA, since the work to create it will be performed externally.


Future work on the Language Subtag Registry includes the following activities:


o Inserting or replacing whole records. These records are preformatted for IANA by the Language Subtag Reviewer, as described in Section 3.3.

o 插入或替换整个记录。如第3.3节所述,这些记录由语言子标签评审员为IANA预先格式化。

o Archiving and making publicly available the registration forms.

o 存档并公开注册表格。

o Announcing each updated version of the registry on the "" mailing list.

o 在“ietf语言”上公布注册表的每个更新版本“邮件列表。

Each registration form sent to IANA contains a single record for incorporation into the registry. The form will be sent to <> by the Language Subtag Reviewer. It will have a subject line indicating whether the enclosed form represents an insertion of a new record (indicated by the word "INSERT" in the subject line) or a replacement of an existing record (indicated by the word "MODIFY" in the subject line). At no time can a record be deleted from the registry.


IANA will extract the record from the form and place the inserted or modified record into the appropriate section of the Language Subtag Registry, grouping the records by their 'Type' field. Inserted records can be placed anywhere within the appropriate section; there is no guarantee that the registry's records will be placed in any particular order except that they will always be grouped by 'Type'. Modified records overwrite the record they replace.

IANA将从表单中提取记录,并将插入或修改的记录放入Language Subtag注册表的相应部分,按记录的“类型”字段对记录进行分组。插入的记录可以放在适当部分的任何位置;不保证注册表的记录将按任何特定顺序排列,除非它们始终按“类型”分组。修改的记录将覆盖它们替换的记录。

Whenever an entry is created or modified in the registry, the 'File-Date' record at the start of the registry is updated to reflect the most recent modification date. The date format SHALL be the "full-date" format of [RFC3339]. The date SHALL be the date on which that version of the registry was first published by IANA. There SHALL be at most one version of the registry published in a day. A 'File-Date' record is also included in each request to IANA to insert or modify records, indicating the acceptance date of the records in the request.


The updated registry file MUST use the UTF-8 character encoding, and IANA MUST check the registry file for proper encoding. Non-ASCII characters can be sent to IANA by attaching the registration form to the email message or by using various encodings in the mail message body (UTF-8 is recommended). IANA will verify any unclear or corrupted characters with the Language Subtag Reviewer prior to posting the updated registry.


IANA will also archive and make publicly available from each registration form. Note that multiple registrations can pertain to the same record in the registry.

IANA还将从 每份登记表。请注意,多个注册可能属于注册表中的同一记录。

Developers who are dependent upon the Language Subtag Registry sometimes would like to be informed of changes in the registry so that they can update their implementations. When any change is made to the Language Subtag Registry, IANA will send an announcement message to <> (a self-subscribing list to which only IANA can post).

依赖于Language Subtag注册表的开发人员有时希望了解注册表中的更改,以便更新其实现。当对语言子标签注册表进行任何更改时,IANA将向<ietf languages]发送公告消息>(只有IANA可以发布的自订阅列表)。

5.2. Extensions Registry
5.2. 扩展注册表

The Language Tag Extensions Registry can contain at most 35 records, and thus changes to this registry are expected to be very infrequent.

Language Tag Extensions注册表最多可以包含35条记录,因此对该注册表的更改预计非常少。

Future work by IANA on the Language Tag Extensions Registry is limited to two cases. First, the IESG MAY request that new records be inserted into this registry from time to time. These requests MUST include the record to insert in the exact format described in Section 3.7. In addition, there MAY be occasional requests from the maintaining authority for a specific extension to update the contact information or URLs in the record. These requests MUST include the complete, updated record. IANA is not responsible for validating the information provided, only that it is properly formatted. IANA SHOULD take reasonable steps to ascertain that the request comes from the maintaining authority named in the record present in the registry.


6. Security Considerations
6. 安全考虑

Language tags used in content negotiation, like any other information exchanged on the Internet, might be a source of concern because they might be used to infer the nationality of the sender, and thus identify potential targets for surveillance.


This is a special case of the general problem that anything sent is visible to the receiving party and possibly to third parties as well. It is useful to be aware that such concerns can exist in some cases.


The evaluation of the exact magnitude of the threat, and any possible countermeasures, is left to each application protocol (see BCP 72 [RFC3552] for best current practice guidance on security threats and defenses).

威胁的确切程度和任何可能的对策的评估由每个应用程序协议决定(有关安全威胁和防御的最佳当前实践指南,请参阅BCP 72[RFC3552])。

The language tag associated with a particular information item is of no consequence whatsoever in determining whether that content might contain possible homographs. The fact that a text is tagged as being in one language or using a particular script subtag provides no assurance whatsoever that it does not contain characters from scripts other than the one(s) associated with or specified by that language tag.


Since there is no limit to the number of variant, private use, and extension subtags, and consequently no limit on the possible length of a tag, implementations need to guard against buffer overflow attacks. See Section 4.4 for details on language tag truncation, which can occur as a consequence of defenses against buffer overflow.


To prevent denial-of-service attacks, applications SHOULD NOT depend on either the Language Subtag Registry or the Language Tag Extensions Registry being always accessible. Additionally, although the specification of valid subtags for an extension (see Section 3.7) MUST be available over the Internet, implementations SHOULD NOT mechanically depend on those sources being always accessible.


The registries specified in this document are not suitable for frequent or real-time access to, or retrieval of, the full registry contents. Most applications do not need registry data at all. For others, being able to validate or canonicalize language tags as of a particular registry date will be sufficient, as the registry contents change only occasionally. Changes are announced to <>. This mailing list is intended for interested organizations and individuals, not for bulk subscription to trigger automatic software updates. The size of the registry makes it unsuitable for automatic software updates. Implementers considering integrating the Language Subtag Registry in an automatic updating scheme are strongly advised to distribute only suitably encoded differences, and only via their own infrastructure -- not directly from IANA.

本文档中指定的注册表不适合频繁或实时访问或检索注册表的全部内容。大多数应用程序根本不需要注册表数据。对于其他人来说,能够在特定注册表日期验证或规范化语言标记就足够了,因为注册表内容只是偶尔更改。已宣布对<ietf语言进行更改>. 此邮件列表适用于感兴趣的组织和个人,而不是批量订阅以触发自动软件更新。注册表的大小使其不适合自动软件更新。强烈建议考虑在自动更新方案中集成语言子标签注册中心的实现者只分发经过适当编码的差异,并且只通过他们自己的基础设施分发,而不是直接从IANA分发。

Changes, or the absence thereof, can also easily be detected by looking at the 'File-Date' record at the start of the registry, or by using features of the protocol used for downloading, without having to download the full registry. At the time of publication of this document, IANA is making the Language Tag Registry available over HTTP 1.1. The proper way to update a local copy of the Language Subtag Registry using HTTP 1.1 is to use a conditional GET [RFC2616].

通过查看注册表开始处的“文件日期”记录,或使用用于下载的协议功能,无需下载完整注册表,也可以轻松检测到更改或缺少更改。在本文档发布时,IANA正在通过HTTP 1.1提供语言标记注册表。使用HTTP 1.1更新语言子标记注册表的本地副本的正确方法是使用条件GET[RFC2616]。

7. Character Set Considerations
7. 字符集注意事项

The syntax in this document requires that language tags use only the characters A-Z, a-z, 0-9, and HYPHEN-MINUS, which are present in most character sets, so the composition of language tags shouldn't have any character set issues.


The rendering of text based on the language tag is not addressed here. Historically, some processes have relied on the use of character set/encoding information (or other external information) in order to infer how a specific string of characters should be rendered. Notably, this applies to language- and culture-specific variations of Han ideographs as used in Japanese, Chinese, and Korean, where use of, for example, a Japanese character encoding such as EUC-JP implies that the text itself is in Japanese. When language tags are applied to spans of text, rendering engines might be able to use that information to better select fonts or make other rendering


choices, particularly where languages with distinct writing traditions use the same characters.


8. Changes from RFC 4646
8. RFC 4646的变更

The main goal for this revision of RFC 4646 was to incorporate two new parts of ISO 639 (ISO 639-3 and ISO 639-5) and their attendant sets of language codes into the IANA Language Subtag Registry. This permits the identification of many more languages and language collections than previously supported.

RFC 4646本次修订的主要目标是将ISO 639的两个新部分(ISO 639-3和ISO 639-5)及其附带的语言代码集纳入IANA语言子标签注册中心。这允许识别比以前支持的更多的语言和语言集合。

The specific changes in this document to meet these goals are:


o Defined the incorporation of ISO 639-3 and ISO 639-5 codes for use as primary and extended language subtags. It also permanently reserves and disallows the use of additional 'extlang' subtags. The changes necessary to achieve this were:

o 定义了ISO 639-3和ISO 639-5代码作为主要和扩展语言子标签的合并。它还永久保留并禁止使用额外的“extlang”子标签。实现这一目标所需的变革包括:

* Modified the ABNF comments.

* 修改了ABNF注释。

* Updated various registration and stability requirements sections to reference ISO 639-3 and ISO 639-5 in addition to ISO 639-1 and ISO 639-2.

* 除ISO 639-1和ISO 639-2外,更新了各种注册和稳定性要求章节,以参考ISO 639-3和ISO 639-5。

* Edited the text to eliminate references to extended language subtags where they are no longer used.

* 编辑文本以消除对不再使用的扩展语言子标签的引用。

* Explained the change in the section on extended language subtags.

* 解释了扩展语言子标签部分中的更改。

o Changed the ABNF related to grandfathered tags. The irregular tags are now listed. Well-formed grandfathered tags are now described by the 'langtag' production, and the 'grandfathered' production was removed as a result. Also: added description of both types of grandfathered tags to Section 2.2.8.

o 更改了与祖父标记相关的ABNF。现在列出了不规则的标记。“langtag”产品现在描述了格式良好的祖父标记,因此“祖父标记”产品被删除。另外:在第2.2.8节中增加了两种类型的祖父标记的描述。

o Added the paragraph on "collections" to Section 4.1.

o 在第4.1节中增加了“收款”一段。

o Changed the capitalization rules for 'Tag' fields in Section 3.1.

o 更改了第3.1节中“标记”字段的大写规则。

o Split Section 3.1 up into subsections.

o 将第3.1节分为几个小节。

o Modified Section 3.5 to allow 'Suppress-Script' fields to be added, modified, or removed via the registration process. This was an erratum from RFC 4646.

o 修改了第3.5节,允许通过注册过程添加、修改或删除“抑制脚本”字段。这是RFC 4646的勘误表。

o Modified examples that used region code 'CS' (formerly Serbia and Montenegro) to use 'RS' (Serbia) instead.

o 将使用地区代码“CS”(前塞尔维亚和黑山)的示例修改为使用“RS”(塞尔维亚)。

o Modified the rules for creating and maintaining record 'Description' fields to prevent duplicates, including inverted duplicates.

o 修改了创建和维护记录“描述”字段的规则,以防止重复,包括反向重复。

o Removed the lengthy description of why RFC 4646 was created from this section, which also caused the removal of the reference to XML Schema.

o 删除了从本节创建RFC4646的详细说明,这也导致删除了对XML模式的引用。

o Modified the text in Section 2.1 to place more emphasis on the fact that language tags are not case sensitive.

o 修改了第2.1节中的文本,以更加强调语言标记不区分大小写这一事实。

o Replaced the example "fr-Latn-CA" in Section 2.1 with "sr-Latn-RS" and "az-Arab-IR" because "fr-Latn-CA" doesn't respect the 'Suppress-Script' on 'Latn' with 'fr'.

o 将第2.1节中的示例“fr Latn CA”替换为“sr Latn RS”和“az Arab IR”,因为“fr Latn CA”不尊重“Latn”上带有“fr”的“抑制脚本”。

o Changed the requirements for well-formedness to make singleton repetition checking optional (it is required for validity checking) in Section 2.2.9.

o 在第2.2.9节中,更改了良好格式的要求,使单例重复检查成为可选的(有效性检查需要进行)。

o Changed the text in Section 2.2.9 referring to grandfathered checking to note that the list is now included in the ABNF.

o 更改了第2.2.9节中提及祖父检查的文本,以注意该列表现在包含在ABNF中。

o Modified and added text to Section 3.2. The job description was placed first. A note was added making clear that the Language Subtag Reviewer may delegate various non-critical duties, including list moderation. Finally, additional text was added to make the appointment process clear and to clarify that decisions and performance of the reviewer are appealable.

o 修改并向第3.2节添加文本。工作描述放在第一位。增加了一个注释,明确了语言子标签评审员可以委派各种非关键职责,包括列表审核。最后,增加了额外的文本,以明确任命流程,并澄清审查人的决定和表现是可上诉的。

o Added text to Section 3.5 clarifying that the list is operated by whomever the IESG appoints.

o 在第3.5节中添加文本,澄清ietf-languages@iana.org该名单由IESG任命的任何人操作。

o Added text to Section 3.1.5 clarifying that the first Description in a 'language' record matches the corresponding Reference Name for the language in ISO 639-3.

o 在第3.1.5节中添加文本,澄清“语言”记录中的第一个描述与ISO 639-3中相应的语言参考名称相匹配。

o Modified Section 2.2.9 to define classes of conformance related to specific tags (formerly 'well-formed' and 'valid' referred to implementations). Notes were added about the removal of 'extlang' from the ABNF provided in RFC 4646, allowing for well-formedness using this older definition. Reference to RFC 3066 well-formedness was also added.

o 修改了第2.2.9节,以定义与特定标记相关的一致性类别(以前的“格式良好”和“有效”指的是实现)。添加了关于从RFC4646中提供的ABNF中删除“extlang”的注释,允许使用此旧定义的良好形式。还增加了对RFC 3066格式良好的参考。

o Added text to the end of Section 3.1.2 noting that future versions of this document might add new field types to the registry format and recommending that implementations ignore any unrecognized fields.

o 在第3.1.2节末尾添加了文本,指出本文档的未来版本可能会向注册表格式添加新的字段类型,并建议实现忽略任何未识别的字段。

o Added text about what the lack of a 'Suppress-Script' field means in a record to Section 3.1.9.

o 在第3.1.9节的记录中添加了关于缺少“抑制脚本”字段意味着什么的文本。

o Added text allowing the correction of misspellings and typographic errors to Section 3.1.5.

o 在第3.1.5节中增加了允许纠正拼写错误和排版错误的文本。

o Added text to Section 3.1.8 disallowing 'Prefix' field conflicts (such as circular prefix references).

o 在第3.1.8节中添加了禁止“前缀”字段冲突的文本(例如循环前缀引用)。

o Modified text in Section 3.5 to require the subtag reviewer to announce his/her decision (or extension) following the two-week period. Also clarified that any decision or failure to decide can be appealed.

o 修改了第3.5节中的文本,要求分包审查员在两周后宣布其决定(或延期)。还澄清,任何决定或未能作出决定均可上诉。

o Modified text in Section 4.1 to include the (heretofore anecdotal) guiding principle of tag choice, and clarifying the non-use of script subtags in non-written applications.

o 修改了第4.1节中的文本,以包括标记选择的(迄今为止的轶事)指导原则,并澄清在非书面应用程序中不使用脚本子标记。

o Prohibited multiple use of the same variant in a tag (i.e., "de-1901-1901"). Previously, this was only a recommendation ("SHOULD").

o 禁止在标签中多次使用同一变体(即“de-1901-1901”)。以前,这只是一项建议(“应该”)。

o Removed inappropriate [RFC2119] language from the illustration in Section 4.4.1.

o 删除了第4.4.1节插图中不适当的[RFC2119]语言。

o Replaced the example of deprecating "zh-guoyu" with "zh-hakka"->"hak" in Section 4.5, noting that it was this document that caused the change.

o 在第4.5节中,用“zh客家”->“hak”替换了不推荐“zh国语”的示例,并指出正是本文件导致了更改。

o Replaced the section in Section 4.1 dealing with "mul"/"und" to include the subtags 'zxx' and 'mis', as well as the tag "i-default". A normative reference to RFC 2277 was added.

o 替换第4.1节中涉及“mul”/“und”的部分,包括子标签“zxx”和“mis”,以及标签“i-default”。增加了对RFC 2277的规范性参考。

o Added text to Section 3.5 clarifying that any modifications of a registration request must be sent to the <> list before submission to IANA.

o 在第3.5节中添加了文本,澄清注册请求的任何修改必须发送给<>提交给IANA之前的列表。

o Changed the ABNF for the record-jar format from using the LWSP production to use a folding whitespace production similar to obs-FWS in [RFC5234]. This effectively prevents unintentional blank lines inside a field.

o 将记录jar格式的ABNF从使用LWSP产品更改为使用折叠空白产品,类似于[RFC5234]中的obs FWS。这可以有效地防止字段内出现意外的空行。

o Clarified and revised text in Sections 3.3, 3.5, and 5.1 to clarify that the Language Subtag Reviewer sends the complete registration forms to IANA, that IANA extracts the record from the form, and that the forms must also be archived separately from the registry.

o 第3.3节、第3.5节和第5.1节中的澄清和修订文本,以澄清语言小组审查员将完整的注册表格发送给IANA,IANA从表格中提取记录,并且表格也必须与注册表分开存档。

o Added text to Section 5 requiring IANA to send an announcement to an ietf-languages-announcements list whenever the registry is updated.

o 在第5节中添加了文本,要求IANA在注册表更新时向ietf语言公告列表发送公告。

o Modification of the registry to use UTF-8 as its character encoding. This also entails additional instructions to IANA and the Language Subtag Reviewer in the registration process.

o 修改注册表以使用UTF-8作为其字符编码。这还需要在注册过程中向IANA和语言子标签评审员提供额外说明。

o Modified the rules in Section 2.2.4 so that "exceptionally reserved" ISO 3166-1 codes other than 'UK' were included into the registry. In particular, this allows the code 'EU' (European Union) to be used to form language tags or (more commonly) for applications that use the registry for region codes to reference this subtag.

o 修改了第2.2.4节中的规则,以便将“例外保留”的ISO 3166-1代码(英国代码除外)纳入注册表。特别是,这允许代码“EU”(欧盟)用于形成语言标记,或(更常见)用于使用registry for region codes引用此子标记的应用程序。

o Modified the IANA considerations section (Section 5) to remove unnecessary normative [RFC2119] language.

o 修改了IANA注意事项部分(第5节),以删除不必要的规范性[RFC2119]语言。

9. References
9. 工具书类
9.1. Normative References
9.1. 规范性引用文件

[ISO15924] International Organization for Standardization, "ISO 15924:2004. Information and documentation -- Codes for the representation of names of scripts", January 2004.

[ISO15924]国际标准化组织,“ISO 15924:2004.信息和文件——脚本名称表示代码”,2004年1月。

[ISO3166-1] International Organization for Standardization, "ISO 3166-1:2006. Codes for the representation of names of countries and their subdivisions -- Part 1: Country codes", November 2006.

[ISO3166-1]国际标准化组织,“ISO 3166-1:2006.国家及其分支机构名称表示代码——第1部分:国家代码”,2006年11月。

[ISO639-1] International Organization for Standardization, "ISO 639-1:2002. Codes for the representation of names of languages -- Part 1: Alpha-2 code", July 2002.

[ISO639-1]国际标准化组织,“ISO 639-1:2002.语言名称表示代码——第1部分:阿尔法-2代码”,2002年7月。

[ISO639-2] International Organization for Standardization, "ISO 639-2:1998. Codes for the representation of names of languages -- Part 2: Alpha-3 code", October 1998.

[ISO639-2]国际标准化组织,“ISO 639-2:1998.语言名称表示代码——第2部分:阿尔法-3代码”,1998年10月。

[ISO639-3] International Organization for Standardization, "ISO 639-3:2007. Codes for the representation of names of languages - Part 3: Alpha-3 code for comprehensive coverage of languages", February 2007.

[ISO639-3]国际标准化组织,“ISO 639-3:2007.语言名称表示代码-第3部分:语言全面覆盖阿尔法-3代码”,2007年2月。

[ISO639-5] International Organization for Standardization, "ISO 639-5:2008. Codes for the representation of names of languages -- Part 5: Alpha-3 code for language families and groups", May 2008.

[ISO639-5]国际标准化组织,“ISO 639-5:2008.语言名称表示代码——第5部分:语言族和语言组的Alpha-3代码”,2008年5月。

[ISO646] International Organization for Standardization, "ISO/IEC 646:1991, Information technology -- ISO 7-bit coded character set for information interchange.", 1991.

[ISO646]国际标准化组织,“ISO/IEC 646:1991,信息技术——信息交换用ISO 7位编码字符集”,1991年。

[RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996.

[RFC2026]Bradner,S.,“互联网标准过程——第3版”,BCP 9,RFC 2026,1996年10月。

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC2119]Bradner,S.,“RFC中用于表示需求水平的关键词”,BCP 14,RFC 2119,1997年3月。

[RFC2277] Alvestrand, H., "IETF Policy on Character Sets and Languages", BCP 18, RFC 2277, January 1998.

[RFC2277]Alvestrand,H.,“IETF字符集和语言政策”,BCP 18,RFC 2277,1998年1月。

[RFC3339] Klyne, G., Ed. and C. Newman, "Date and Time on the Internet: Timestamps", RFC 3339, July 2002.


[RFC4647] Phillips, A. and M. Davis, "Matching of Language Tags", BCP 47, RFC 4647, September 2006.

[RFC4647]Phillips,A.和M.Davis,“语言标记的匹配”,BCP 47,RFC 4647,2006年9月。

[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.

[RFC5226]Narten,T.和H.Alvestrand,“在RFCs中编写IANA注意事项部分的指南”,BCP 26,RFC 5226,2008年5月。

[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008.

[RFC5234]Crocker,D.和P.Overell,“语法规范的扩充BNF:ABNF”,STD 68,RFC 5234,2008年1月。

[SpecialCasing] The Unicode Consoritum, "Unicode Character Database, Special Casing Properties", March 2008, <http://>.


[UAX14] Freitag, A., "Unicode Standard Annex #14: Line Breaking Properties", August 2006, <>.


[UN_M.49] Statistics Division, United Nations, "Standard Country or Area Codes for Statistical Use", Revision 4 (United Nations publication, Sales No. 98.XVII.9, June 1999.


[Unicode] Unicode Consortium, "The Unicode Consortium. The Unicode Standard, Version 5.0, (Boston, MA, Addison-Wesley, 2003. ISBN 0-321-49081-0)", January 2007.

[Unicode]Unicode联合会,“Unicode联合会。Unicode标准,5.0版,(马萨诸塞州波士顿市,Addison-Wesley,2003年。ISBN 0-321-49081-0)”,2007年1月。

9.2. Informative References
9.2. 资料性引用

[CLDR] "The Common Locale Data Repository Project", <>.


[RFC1766] Alvestrand, H., "Tags for the Identification of Languages", RFC 1766, March 1995.


[RFC2028] Hovey, R. and S. Bradner, "The Organizations Involved in the IETF Standards Process", BCP 11, RFC 2028, October 1996.

[RFC2028]Hovey,R.和S.Bradner,“参与IETF标准过程的组织”,BCP 11,RFC 2028,1996年10月。

[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996.

[RFC2046]Freed,N.和N.Borenstein,“多用途Internet邮件扩展(MIME)第二部分:媒体类型”,RFC 20461996年11月。

[RFC2047] Moore, K., "MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text", RFC 2047, November 1996.

[RFC2047]Moore,K.,“MIME(多用途互联网邮件扩展)第三部分:非ASCII文本的消息头扩展”,RFC 2047,1996年11月。

[RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations", RFC 2231, November 1997.

[RFC2231]Freed,N.和K.Moore,“MIME参数值和编码字扩展:字符集、语言和连续体”,RFC 22311997年11月。

[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

[RFC2616]菲尔丁,R.,盖蒂斯,J.,莫卧儿,J.,弗莱斯蒂克,H.,马斯特,L.,利奇,P.,和T.伯纳斯李,“超文本传输协议——HTTP/1.1”,RFC 2616,1999年6月。

[RFC2781] Hoffman, P. and F. Yergeau, "UTF-16, an encoding of ISO 10646", RFC 2781, February 2000.

[RFC2781]Hoffman,P.和F.Yergeau,“UTF-16,ISO 10646编码”,RFC 2781,2000年2月。

[RFC3066] Alvestrand, H., "Tags for the Identification of Languages", RFC 3066, January 2001.

[RFC3066]Alvestrand,H.,“语言识别标签”,RFC 3066,2001年1月。

[RFC3282] Alvestrand, H., "Content Language Headers", RFC 3282, May 2002.

[RFC3282]Alvestrand,H.,“内容语言标题”,RFC 3282,2002年5月。

[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC Text on Security Considerations", BCP 72, RFC 3552, July 2003.

[RFC3552]Rescorla,E.和B.Korver,“关于安全考虑的RFC文本编写指南”,BCP 72,RFC 3552,2003年7月。

[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003.

[RFC3629]Yergeau,F.,“UTF-8,ISO 10646的转换格式”,STD 63,RFC 3629,2003年11月。

[RFC4645] Ewell, D., "Initial Language Subtag Registry", RFC 4645, September 2006.

[RFC4645]Ewell,D.,“初始语言子标签注册”,RFC 46452006年9月。

[RFC4646] Phillips, A. and M. Davis, "Tags for Identifying Languages", BCP 47, RFC 4646, September 2006.

[RFC4646]Phillips,A.和M.Davis,“识别语言的标记”,BCP 47,RFC 46462006年9月。

[RFC5645] Ewell, D., Ed., "Update to the Language Subtag Registry", September 2009.


[UTS35] Davis, M., "Unicode Technical Standard #35: Locale Data Markup Language (LDML)", December 2007, <>.


[iso639.prin] ISO 639 Joint Advisory Committee, "ISO 639 Joint Advisory Committee: Working principles for ISO 639 maintenance", March 2000, < standards/iso639-2/iso639jac_n3r.html>.

[iso639.prin]ISO 639联合咨询委员会,“ISO 639联合咨询委员会:ISO 639维护工作原则”,2000年3月< 标准/iso639-2/iso639jac_n3r.html>。

[record-jar] Raymond, E., "The Art of Unix Programming", 2003, <urn:isbn:0-13-142901-9>.

[record jar]Raymond,E.,“Unix编程的艺术”,2003年,<urn:isbn:0-13-142901-9>。

Appendix A. Examples of Language Tags (Informative)


Simple language subtag:


de (German)


fr (French)


ja (Japanese)


i-enochian (example of a grandfathered tag)


Language subtag plus Script subtag:


zh-Hant (Chinese written using the Traditional Chinese script)

zh Hant(繁体中文书写)

zh-Hans (Chinese written using the Simplified Chinese script)

zh Hans(简体中文书写)

sr-Cyrl (Serbian written using the Cyrillic script)

sr Cyrl(塞尔维亚语,使用西里尔文书写)

sr-Latn (Serbian written using the Latin script)


Extended language subtags and their primary language subtag counterparts:


zh-cmn-Hans-CN (Chinese, Mandarin, Simplified script, as used in China)

zh cmn Hans CN(中文、普通话、简体字,在中国使用)

cmn-Hans-CN (Mandarin Chinese, Simplified script, as used in China)

cmn Hans CN(中国使用的简体中文普通话)

zh-yue-HK (Chinese, Cantonese, as used in Hong Kong SAR)


yue-HK (Cantonese Chinese, as used in Hong Kong SAR)




zh-Hans-CN (Chinese written using the Simplified script as used in mainland China)

zh Hans CN(中国大陆使用的简体中文书写)

sr-Latn-RS (Serbian written using the Latin script as used in Serbia)

sr Latn RS(塞尔维亚语,使用塞尔维亚语中使用的拉丁语书写)



sl-rozaj (Resian dialect of Slovenian)

sl rozaj(斯洛文尼亚的雷斯安方言)

sl-rozaj-biske (San Giorgio dialect of Resian dialect of Slovenian)

sl rozaj biske(斯洛文尼亚Resian方言的圣乔治方言)

sl-nedis (Nadiza dialect of Slovenian)

sl nedis(斯洛文尼亚的纳迪扎方言)



de-CH-1901 (German as used in Switzerland using the 1901 variant [orthography])


sl-IT-nedis (Slovenian as used in Italy, Nadiza dialect)

sl IT nedis(意大利使用的斯洛文尼亚语,纳迪扎方言)



hy-Latn-IT-arevela (Eastern Armenian written in Latin script, as used in Italy)

hy-Latn IT arevela(用拉丁语书写的东亚美尼亚语,在意大利使用)



de-DE (German for Germany)


en-US (English as used in the United States)

en US(美国使用的英语)

es-419 (Spanish appropriate for the Latin America and Caribbean region using the UN region code)


Private use subtags:






Private use registry values:


x-whatever (private use using the singleton 'x')


qaa-Qaaa-QM-x-southern (all private tags)


de-Qaaa (German, with a private script)

de Qaaa(德语,带私人脚本)

sr-Latn-QM (Serbian, Latin script, private region)


sr-Qaaa-RS (Serbian, private script, for Serbia)

sr Qaaa RS(塞尔维亚语,私人脚本,塞尔维亚语)

Tags that use extensions (examples ONLY -- extensions MUST be defined by revision or update to this document, or by RFC):








Some Invalid Tags:


de-419-DE (two region tags)


a-DE (use of a single-character subtag in primary position; note that there are a few grandfathered tags that start with "i-" that are valid)


ar-a-aaa-b-bbb-a-ccc (two extensions with same single-letter prefix)


Appendix B. Examples of Registration Forms



1. Name of requester: Han Steenwijk 2. E-mail address of requester: han.steenwijk @ 3. Record Requested:

1. 申请人姓名:Han Steenwijk 2。请求者的电子邮件地址 3。要求的记录:

Type: variant Subtag: biske Description: The San Giorgio dialect of Resian Description: The Bila dialect of Resian Prefix: sl-rozaj Comments: The dialect of San Giorgio/Bila is one of the four major local dialects of Resian

类型:变体子标签:biske描述:Resian的San Giorgio方言描述:Resian的Bila方言前缀:sl rozaj注释:San Giorgio/Bila方言是Resian四大地方方言之一

4. Intended meaning of the subtag:

4. 子标签的预期含义:

The local variety of Resian as spoken in San Giorgio/Bila


5. Reference to published description of the language (book or article):

5. 参考已出版的语言描述(书籍或文章):

-- Jan I.N. Baudouin de Courtenay - Opyt fonetiki rez'janskich govorov, Varsava - Peterburg: Vende - Kozancikov, 1875.




1. Name of requester: Jaska Zedlik 2. E-mail address of requester: jz53 @ 3. Record Requested:

1. 申请人姓名:Jaska Zedlik 2。请求者的电子邮件地址 3。要求的记录:

Type: variant Subtag: tarask Description: Belarusian in Taraskievica orthography Prefix: be Comments: The subtag represents Branislau Taraskievic's Belarusian orthography as published in "Bielaruski klasycny pravapis" by Juras Buslakou, Vincuk Viacorka, Zmicier Sanko, and Zmicier Sauka (Vilnia-Miensk 2005).

类型:变体子标签:塔拉斯克描述:塔拉斯基耶维奇正字法中的白俄罗斯语前缀:be注释:子标签代表布拉尼斯劳·塔拉斯基耶维奇的白俄罗斯语正字法,由Juras Buslakou、Vincuk Viacocka、Zmicier Sanko和Zmicier Sauka(Vilnia Miensk 2005)在“Bielaruski Klasyny pravapis”中发表。

4. Intended meaning of the subtag:

4. 子标签的预期含义:

The subtag is intended to represent the Belarusian orthography as published in "Bielaruski klasycny pravapis" by Juras Buslakou, Vincuk Viacorka, Zmicier Sanko, and Zmicier Sauka (Vilnia-Miensk 2005).

子标签旨在代表Juras Buslakou、Vincuk Viacocka、Zmicier Sanko和Zmicier Sauka在“Bielaruski Klasyny pravapis”中发表的白俄罗斯正字法(Vilnia Miensk 2005)。

5. Reference to published description of the language (book or article):

5. 参考已出版的语言描述(书籍或文章):

Taraskievic, Branislau. Bielaruskaja gramatyka dla skol. Vilnia: Vyd. "Bielaruskaha kamitetu", 1929, 5th edition.

塔拉斯基耶维奇,布拉尼斯劳。比亚拉鲁斯卡亚·格拉马蒂卡·德拉斯卡尔。维尼亚:维德。“Bielaruskaha kamitetu”,1929年,第5版。

Buslakou, Juras; Viacorka, Vincuk; Sanko, Zmicier; Sauka, Zmicier. Bielaruski klasycny pravapis. Vilnia-Miensk, 2005.


6. Any other relevant information:

6. 任何其他相关信息:

Belarusian in Taraskievica orthography became widely used, especially in Belarusian-speaking Internet segment, but besides this some books and newspapers are also printed using this orthography of Belarusian.


Appendix C. Acknowledgements

Any list of contributors is bound to be incomplete; please regard the following as only a selection from the group of people who have contributed to make this document what it is today.


The contributors to RFC 4646, RFC 4647, RFC 3066, and RFC 1766, the precursors of this document, made enormous contributions directly or indirectly to this document and are generally responsible for the success of language tags.

本文档的前身RFC 4646、RFC 4647、RFC 3066和RFC 1766的贡献者直接或间接地为本文档做出了巨大贡献,并且通常对语言标记的成功负责。

The following people contributed to this document:


Stephane Bortzmeyer, Karen Broome, Peter Constable, John Cowan, Martin Duerst, Frank Ellerman, Doug Ewell, Deborah Garside, Marion Gunn, Alfred Hoenes, Kent Karlsson, Chris Newman, Randy Presuhn, Stephen Silver, Shawn Steele, and many, many others.


Very special thanks must go to Harald Tveit Alvestrand, who originated RFCs 1766 and 3066, and without whom this document would not have been possible.

必须特别感谢Harald Tveit Alvestrand,他是RFC 1766和3066的发起人,没有他,本文件就不可能完成。

Special thanks go to Michael Everson, who served as the Language Tag Reviewer for almost the entire RFC 1766/RFC 3066 period, as well as the Language Subtag Reviewer since the adoption of RFC 4646.

特别感谢Michael Everson,他几乎在整个RFC 1766/RFC 3066期间担任语言标签评审员,以及自RFC 4646采用以来担任语言子标签评审员。

Special thanks also go to Doug Ewell, for his production of the first complete subtag registry, his work to support and maintain new registrations, and his careful editorship of both RFC 4645 and [RFC5645].

还要特别感谢Doug Ewell,他制作了第一个完整的subtag注册表,支持和维护新注册的工作,以及他对RFC 4645和[RFC5645]的精心编辑。

Authors' Addresses


Addison Phillips (editor) Lab126



Mark Davis (editor) Google