<rt>

<rt> (ruby text) contains a ruby text, an annotation closely associated with a passage of the main text. [3.4.2 Ruby Annotations]
Module core — Elements Available in All TEI Documents
Attributes
target⚓︎ supplies a pointer to the base being glossed by this ruby text.
Status Optional
Datatype teidata.pointer
Schematron Enforce that either target or both from and to (or none) are used, but not target in combination with either from or to.

<sch:report test="../@from | ../@to">When target= is
present, neither from= nor to= should be.</sch:report>
Note

Should point to a single rb or an element that is inside an rb. To refer to multiple elements or text nodes at once use from and to.
from⚓︎ points to the starting point of the span of text being glossed by this ruby text.
Status Optional
Datatype teidata.pointer
Schematron Enforce the presence of to iff there is a from.

<sch:assert test="../@to">When from= is present, the to=
attribute of <sch:name/> is required.</sch:assert>
to⚓︎ points to the ending point of the span of text being glossed.
Status Optional
Datatype teidata.pointer
Schematron Enforce the presence of from iff there is a to.

<sch:assert test="../@from">When to= is present, the from=
attribute of <sch:name/> is required.</sch:assert>
Contained by
core: ruby
May contain
analysis: c cl interp interpGrp m pc phr s span spanGrp w
certainty: certainty precision respons
core: abbr add address binaryObject cb choice cit corr date del distinct ellipsis email emph expan foreign gap gb gloss graphic hi index lb measure measureGrp media mentioned milestone name note noteGrp num orig pb ptr q quote ref reg rs ruby said sic soCalled term time title unclear unit
dictionaries: lang oRef pRef
figures: figure formula notatedMusic
gaiji: g
header: idno
iso-fs: fLib fs fvLib
linking: alt altGrp anchor join joinGrp link linkGrp seg timeline
msdescription: catchwords depth dim dimensions height heraldry locus locusGrp material objectType origDate origPlace secFol signatures stamp watermark width
namesdates: addName affiliation bloc climate country district eventName forename genName geo geogFeat geogName location nameLink objectName offset orgName persName persPronouns placeName population region roleName settlement state surname terrain trait
spoken: incident kinesic pause shift vocal writing
tagdocs: att code gi ident listRef specDesc specList tag val
textcrit: app witDetail
textstructure: floatingText
transcr: addSpan am damage damageSpan delSpan ex fw handShift listTranspose metamark mod redo restore retrace secl space subst substJoin supplied surplus undo
verse: caesura rhyme
character data
Note

Where the place attribute is not provided on the rt element, the default assumption is that the ruby gloss is above where the text is horizontal, and to the right of the text where it is vertical.
Example

The word 大統領 daitōryō (president) is glossed character by character in hiragana to provide a pronunciation guide.

<p style="writing-mode: vertical-rl"
 xml:lang="ja">
<!--...-->
 <ruby>
  <rb>大</rb>
  <rt place="right">だい</rt>
 </ruby>
 <ruby>
  <rb>統</rb>
  <rt place="right">とう</rt>
 </ruby>
 <ruby>
  <rb>領</rb>
  <rt place="right">りょう</rt>
 </ruby>
<!--...-->
</p>
Content model 
<content>
 <macroRef key="macro.phraseSeq"/>
</content>
Schema Declaration 
<rng:element name="rt">
 <rng:ref name="att.global.attributes"/>
 <rng:ref name="att.global.rendition.attributes"/>
 <rng:ref name="att.global.linking.attributes"/>
 <rng:ref name="att.global.analytic.attributes"/>
 <rng:ref name="att.global.facs.attributes"/>
 <rng:ref name="att.global.change.attributes"/>
 <rng:ref name="att.global.responsibility.attributes"/>
 <rng:ref name="att.global.source.attributes"/>
 <rng:ref name="att.typed.attributes"/>
 <rng:ref name="att.placement.attributes"/>
 <rng:ref name="att.transcriptional.attributes"/>
 <rng:ref name="att.editLike.attributes"/>
 <rng:ref name="att.written.attributes"/>
 <rng:optional>
  <rng:attribute name="target">
   <rng:ref name="teidata.pointer"/>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="from">
   <rng:ref name="teidata.pointer"/>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="to">
   <rng:ref name="teidata.pointer"/>
  </rng:attribute>
 </rng:optional>
 <rng:ref name="macro.phraseSeq"/>
</rng:element>
element rt
{
   att.global.attributes,
   att.global.rendition.attributes,
   att.global.linking.attributes,
   att.global.analytic.attributes,
   att.global.facs.attributes,
   att.global.change.attributes,
   att.global.responsibility.attributes,
   att.global.source.attributes,
   att.typed.attributes,
   att.placement.attributes,
   att.transcriptional.attributes,
   att.editLike.attributes,
   att.written.attributes,
   attribute target { teidata.pointer }?,
   attribute from { teidata.pointer }?,
   attribute to { teidata.pointer }?,
   macro.phraseSeq
}