The example nav is an unordered list for a max of 2 levels of nesting for ExpressionEngine Taxonomy plugin

Bootstrap3 nav with Taxonomy3

<ul class="navbar-collapse bs-navbar-collapse collapse" role="navigation">
    {exp:taxonomy:nav 
		tree_id="2" 
		display_root="no"
		style="linear"
	}
	<li{if node_has_children} class="has-dropdown"{/if}>
        <a href="{node_url}"
            {if target_blank} target="_blank"{/if}
            {if title_attribute} title="{title_attribute}"{/if}
            {if node_has_children} id="drop{node_level_count}" class="dropdown-toggle" data-toggle="dropdown"{/if}>
            {node_title}
            {if node_has_children}<b class="caret"></b>{/if}
        </a>
        {if node_has_children}
		<ul class="dropdown" role="menu" aria-labelledby="drop{node_level_count}">
            {children}
        </ul>
        {/if}
    </li>
	{/exp:taxonomy:nav}
</ul>