that; those; commonly pr. nei4 before a classifier, esp. in Beijing[cedict]
是
shìㄕˋ
is; are; am; yes; to be[cedict]
对牛弹琴
duì niú tán qínㄉㄨㄟˋ ㄋㄧㄡˊ ㄊㄢˊ ㄑㄧㄣˊ
to play the lute to a cow (成语 saw); 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[cedict]