不ㄅㄨˋbù知ㄓzhī輕ㄑㄧㄥqīng重ㄓㄨㄥˋzhòng

  1. 不知事情的輕重，有冒昧的意思。《紅樓夢·第一○九回》：「婆子們不知輕重，說是這兩日有些病，恐不能就好，到這裡問大夫。」

客毋知重輕
英lit. not knowing what's important (idiom)​; no appreciation of the gravity of things, naive, doesn't know who's who, no sense of priorities