<ruby>: The Ruby Annotation element - HTML

Try it

<ruby> 明日 <rp>(</rp><rt>Ashita</rt><rp>)</rp> </ruby>

This element only includes the global attributes.

<ruby>
  漢 <rp>(</rp><rt>Kan</rt><rp>)</rp> 字 <rp>(</rp><rt>ji</rt><rp>)</rp>
</ruby>

<ruby> 明日 <rp>(</rp><rt>Ashita</rt><rp>)</rp> </ruby>

Content categories	Flow content, phrasing content, palpable content.
Permitted content	One or more groups, each consisting of two parts: The base text, which is either: Phrasing content, but with no `<ruby>` elements and with no `<ruby>` element descendants, or A single `<ruby>` element that itself has no `<ruby>` element descendants. The annotations for the base text, which is either: One or more `<rt>` elements, or An `<rp>` element followed by one or more `<rt>` elements, each of which is itself followed by an `<rp>` element (that is, `rp, rt, rp, rt, ..., rp`).
Tag omission	None, both the starting and ending tag are mandatory.
Permitted parents	Any element that accepts phrasing content.
Implicit ARIA role	No corresponding role
Permitted ARIA roles	Any
DOM interface	`HTMLElement`

Specification
HTML # the-ruby-element