public static function tokenize($sentence, $options = array("HMM" => true))
    {
        $seg_list = self::cut($sentence, false, array("HMM" => $options["HMM"]));
        $tokenize_list = [];
        $start = 0;
        $end = 0;
        foreach ($seg_list as $seg) {
            $end = $start+mb_strlen($seg, 'UTF-8');
            $tokenize = [
                'word' => $seg,
                'start' => $start,
                'end' => $end
            ];
            $start = $end;
            array_push($tokenize_list, $tokenize);
        }
        return $tokenize_list;
    }