function multi_exact ($letexte, $lang=null) {
    if (!$lang) $lang = $GLOBALS["lang"];

    if (preg_match_all(_EXTRAIRE_MULTI, $letexte, $regs, PREG_SET_ORDER)) {
        foreach ($regs as $reg) {
            $trads = extraire_trads($reg[1]);

            if ($l = approcher_langue($trads, $lang)) {
                $trad = $trads[$l];
            } else {
                $trad = $trads[""];
            }
            $letexte = str_replace($reg[0], trim($trad), $letexte);
        }
    }
    return $letexte;
}