<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<div class="dropdown">
<button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown">Tutorials
<span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a tabindex="-1" href="#">HTML</a></li>
<li><a tabindex="-1" href="#">CSS</a></li>
<li class="dropdown-submenu">
<a class="test" tabindex="-1" href="#">New dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a tabindex="-1" href="#">2nd level dropdown</a></li>
<li><a tabindex="-1" href="#">2nd level dropdown</a></li>
<li class="dropdown-submenu">
<a class="test" href="#">Another dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">3rd level dropdown</a></li>
<li><a href="#">3rd level dropdown</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</div>