怎么可以让多行同时隐藏？

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<table width="300" border="0" cellspacing="0" cellpadding="0">
  <tr> 
    <td>a</td>
    <td>b</td>
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  <tr> 
    <td>c</td>
    <td>d</td>
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  <tbody id="tt" style="display:none">
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    <td>e</td>
    <td>f</td>
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  <tr> 
    <td>g</td>
    <td>h</td>
  </tr>
  <tr>
    <td>i</td>
    <td>j</td>
  </tr>
  </tbody>
  <tr>
    <td>k</td>
    <td>l</td>
  </tr>
</table>
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