The following:
use HTML::TreeBuilder;
my $html = "
<table>
<tr><td><p></td></tr>
<tr><td></td></tr>
</table>";
my $tb = new HTML::TreeBuilder;
$tb->parse( $html );
$tb->dump;
Generated (note the additional <TABLE> tag):
$ co.pl
<HTML>
" "
<BODY>
<P>
<TABLE>
" "
<TR>
<TD>
<P>
" "
<TABLE>
<TR>
<TD>
" "
-sls