<sub>
This tag is supported by generative, long-form, neural, and standard TTS formats.
Use the <sub> tag with the alias
attribute to substitute a different word (or pronunciation) for
selected text such as an acronym or abbreviation.
This uses the syntax:
<sub alias="new word">abbreviation</sub>In the following example, the name "Mercury" is substituted for the element's chemical symbol to make the audio content clearer.
<speak> My favorite chemical element is <sub alias="Mercury">Hg</sub>, because it looks so shiny. </speak>
