雷ㄌㄟˊléi打ㄉㄚˇdǎ不ㄅㄨˋbù動ㄉㄨㄥˋdòng

  1. 比喻意志堅定，不可動搖。如：「他心如鐵鑄，雷打不動。」

  2. 比喻做事嚴遵規矩，決不變更。如：「他一向是軍令如山，雷打不動。」

英not shaken by thunder (idiom)​; the arrangements are unalterable, to adhere rigidly to regulations, will go ahead whatever happens (of an arrangement or plan)​