The <keepTogether>tag tries to keep two elements together. This means when there is a page break both elements would move to the next page. This is approximate, so it sometimes will not work.
It can only be used within a .
Example
...
<keepTogether>
<text>Headline of the following table
</text>
<table>
<tr>
<td>SOME LONG TEXT</td>
</tr>
</table>
</keepTogether>
...
