DICT.TW Dictionary Taiwan

 對牛彈琴 [ㄉㄨㄟˋ ㄋㄧㄡˊ ㄊㄢˊ ㄑㄧㄣˊ; dui4 niu2 tan2 qin2]
 to play the lute to a cow (idiom); fig. offering a treat to a unappreciative audience
 to cast pearls before swine
 caviar to the general
 to preach to deaf ears
 to talk over sb's head
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