jwv

<?php 	
function highlight($astring, $aword) {
	if (!is_array ($aword) || !is_string ($astring) || empty ($aword) ) {
    	return false;
        }

        $aword = implode ('|', $aword);
        return preg_replace ('@\b('.$aword.')\b@si', '<strong style="background-color:red">$1</strong>', $astring);
}