My function is changing $word_one (je/que je in j'/que j'), if $word_two begins with a vowel.
function FrenchCompoundTenses($word_one, $word_two) {
if(preg_match('~(.*)\bje$~ui', $word_one, $m) && preg_match('~^[aeéiou]~ui>', $word_two)) 
    return "<td class=\"text-right text-muted\">{$m[1]}j'</td>" . $word_two;               
else 
    return "<td class=\"text-right text-muted\">". $word_one ."</td>" . $word_two;
}  
For a similar function I have to change this part:
&& preg_match('~^[aeéiou]~ui>', $word_two) 
It should worked, if $word_two begin with HTML code <u> or </td><td>  and then a vowel is following.([aeéiou])
EDIT: $word_one comes from an array with pronoun and $word_two comes from a 2-dimensional array. $word_two are in this case two words.
example:
 $word_one= 'je' +   $word_two='aime'  =  j'aime 
 $word_one= 'tu' +   $word_two='aimes' = tu aimes 
desired output with this function:
 $word_one= 'je' +   $word_two='<u>aime' = j'aime (with html code between)
 $word_one= 'je' +   $word_two='</td><td>aime' = j'aime (with html code between)
				
                        
&& preg_match('~^h?(?:[aæàâeéèêëiîïoôœuûù]|y(?![aæàâeéèêëiîïoôœuûù]))~ui', strip_tags($word_two))should solve the problem.(I added an optional
hat the begining sincehis a silenthin french. I added too several accented vowels) and theywhen not followed by another vowel.