Modal Box无法打开

Question

我试图在使用twitter bootstrap 3.0点击按钮时打开一个模态框。但是，单击按钮时，没有显示模态框。

<tr>
   <td height=150>
     <button type="button" class="btn btn-primary btn-lg btn-block" data-toggle="modal" href="#myModal" >Anonymous Question</button>
   </td>  
</tr>   

// the modal code
<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>
<!-- Modal End -->