permutability
词形变化：
动词过去式: permed | 动词过去分词: permed | 动词现在分词: perming | 动词第三人称单数: perms |
同义词：
let | allow | licence | license | authorize | document | certification | certificate | authorization | consent to | approve | OK | agree to | sanction | pass | grant | admit | consent | tolerate | permission | countenance | leave |
反义词：