要用bootstrap做一个侧边栏还要能展开二级菜单，求问大神们怎么做？

Question

<div class="form-group col-md-6 col-sm-6" style="width:30%">

<label class="col-sm-4 control-label" style="text-align: left"><h4><strong>有偿使用:</strong></h4></label>

<div class="col-sm-8">

<select class="form-control" name="sy">

<option value="1">计费</option>

<option value="2">收费</option>

</select>

</div>

</div>

<div class="form-group col-md-6 col-sm-6" style="width:30%">

<label class="col-sm-4 control-label" style="text-align: left"><h4><strong>有偿退出:</strong></h4></label>

<div class="col-sm-8">

<select class="form-control" name="tc">

<option value="1">补偿</option>

<option value="2">补助</option>

 

</select>

</div>

</div>

这是之前写成下拉菜单，求问大神们改成侧边栏。跪求！