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Text Encoding Initiative

The XML Version of the TEI Guidelines

<language>

<language> characterizes a single language or sublanguage used within a text.
Attributes (In addition to global attributes)
wsd specifies the entity containing the writing system declaration used for representing texts in this language.
Datatype: ENTITY
Values: the named entity should contain a full writing system declaration conforming to the auxiliary WSD document type declaration.
Default: #IMPLIED
Note

On this element, the global id attribute specifies the identifier for the writing system declaration for this language (e.g. eng, fra, deu). Its value will usually be a language identifier from ISO 639, possibly extended to indicate the writing system in use (e.g. heb-hel for Hebrew written in Greek.

The entity containing the writing system declaration will typically be an external (unparsed) entity; it must be declared in the DTD.
usage specifies the approximate percentage (by volume) of the text which uses this language.
Datatype: CDATA
Values: a whole number between 1 and 100
Default: #IMPLIED
Example 
<language id="lap" usage="100">Pig Latin</language>
Module Declared in file teihdr2; Core tag sets: enabled when any TEI base is enabled
Data Description Particularly for sublanguages, an informal prose characterization should be supplied as content for the element in addition to the specification implied by the WSD
May contain #PCDATA abbr add addSpan address alt altGrp anchor app c caesura cb certainty cl corr damage date dateRange dateStruct del delSpan distinct emph expan fLib foreign formula fs fsLib fvLib fw gap geogName gloss handShift hi index interp interpGrp join joinGrp lang lb link linkGrp m measure mentioned milestone name num oRef oVar orgName orig pRef pVar pb persName phr placeName ptr ref reg respons restore rs s seg sic soCalled space span spanGrp supplied term time timeRange timeStruct timeline title unclear w xptr xref
May occur within langUsage
Declaration 
<!ELEMENT language %om.RO; %phrase.seq;> 
<!ATTLIST language  
      %a.global;
      wsd ENTITY #IMPLIED
      usage CDATA #IMPLIED>
See further 5.4.2 Language Usage

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