I would like that to be matched as well.
I have done something like this so far
$noTags = strip_tags($text);
$withEm = str_replace($_GET['sq'], '<em>'.$_GET['sq'].'</em>', $noTags);
print '<p>'.substr($withEm, 0 , 100).'...</p>';
$pos = strrpos($withEm, $_GET['sq']);
if (!($pos === false)){...