对牛弹琴
to cast pearls before swine; wasting effort on an unappreciative audience
HSK 7-9
Pronunciation
duìniú-tánqín
Example sentence
跟他讲文学简直是对牛弹琴,他根本不感兴趣。
Talking to him about literature is like casting pearls before swine; he has no interest at all.
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