crodas\TextRank\POS\English\Tagger::get PHP Method

    public static function get(array $words)
    {
        return array_map(function ($word) {
            return $word['token'];
        }, array_filter(self::tag($words), function ($word) {
            switch ($word['tag']) {
                case 'NN':
                case 'JJ':
                case 'NNP':
                case 'NNS':
                    return true;
            }
            return false;
        }));
    }