对 dui4 對
牛 niu2 牛
弹 tan2 彈
琴 qin2 琴
  1. lit. to play the lute to a cow (idiom)
  2. fig. offering a treat to an unappreciative audience
  3. to cast pearls before swine
  4. caviar to the general
  5. to preach to deaf ears
  6. to talk over sb's head

Info