Use the <emph> element (emphasis) as shown:
<emph> text <\emph>
!! text !!
Emphasized text is displayed using an italic font.
Here's how you might emphasize an important word:
A thousand times <emph>no<\emph>
Or, using the shorthand form:
A thousand times !!no!!
In both cases, the word "no" is displayed in italics.