1<p>One asterisk: *</p>
2<p>One underscore: _</p>
3<p>Two asterisks: **</p>
4<p>With spaces: * *</p>
5<p>Two underscores __</p>
6<p>with spaces: _ _</p>
7<p>three asterisks: ***</p>
8<p>with spaces: * * *</p>
9<p>three underscores: ___</p>
10<p>with spaces: _ _ _</p>