showdown/test/cases/emphasis.html

<p><em>single asterisks</em></p>

<p><em>single underscores</em></p>

<p><strong>double asterisks</strong></p>

<p><strong>double underscores</strong></p>

<p>text <em>with italic sentence</em> in middle</p>

<p>text <strong>with bold sentence</strong> in middle</p>

<p>text with <strong>bold text that
spans across multiple</strong> lines</p>