把两个表头单元格规定为列的表头 - 在线编辑器

          <table border="1">
  <tr>
    <th></th>
    <th scope="col">Month</th>
    <th scope="col">Savings</th>
  </tr>
  <tr>
    <td>1</td>
    <td>January</td>
    <td>$100</td>
  </tr>
  <tr>
    <td>2</td>
    <td>February</td>
    <td>$80</td>
  </tr>
</table>
        