Cómo agregar varias filas dentro de una fila en HTML
<table>
<tr>
<td >ID</td>
<td>SEC</td>
<td>DIV</td>
</tr>
<tr>
<td rowspan="3">1</td>
<td>S1</td>
<td>D1</td>
</tr>
<tr>
<td>S2</td>
<td>D2</td>
</tr>
<tr>
<td>S3</td>
<td>D3</td>
</tr>
<tr><td colspan="3">---------------------</td></tr>
<tr>
<td>ID</td>
<td>SEC</td>
<td>DIV</td>
</tr>
<tr>
<td rowspan="3">2</td>
<td>S1</td>
<td>D1</td>
</tr>
<tr>
<td>S2</td>
<td>D2</td>
</tr>
<tr>
<td>S3</td>
<td>D3</td>
</tr>
</table>
vasilaking