private static function step0a($word)
    {
        $vstr = implode('', self::$vowels);
        $word = preg_replace('#([' . $vstr . '])u([' . $vstr . '])#u', '$1U$2', $word);
        $word = preg_replace('#([' . $vstr . '])y([' . $vstr . '])#u', '$1Y$2', $word);

        return $word;
    }