teach /tiːtʃ/► SEE ALLteach your grandmother to suck eggsteach sb a lesson(you can’t) teach an old dog new trickscan/could teach/tell sb a thing or two (about sb/sth) ●teach your grandmother to suck ˈeggs (BrE, informal) tell or show sb how to do sth that they can already do well, and probably better than you can在能人面前逞强；班门弄斧◆I don’t know why he’s telling Rob how to use the computer. It seems to me like teaching your grandmother to suck eggs. 我不知道他何以教罗布用计算机，我看这简直就是教鱼游泳嘛。●teach sb a ˈlesson ( ˈteach sb (to do sth)) learn from a punishment or because of an unpleasant experience, that you have done sth wrong or made a mistake给某人一个教训◆He needs to be taught a lesson (= he should be punished). 该好好教训他一顿。◆Losing all his money in a card game has taught him a lesson he’ll never forget. 玩牌把钱全输光了，这给了他一个永远难忘的教训。◆That’ll teach you! Perhaps you’ll be more careful in future! 这对你是个教训！也许以后你会小心些了！●(you can’t) teach an old dog new ˈtricks (saying) (you can’t) make old people change their ideas or ways of working, etc.（无法）改变老人的想法（或积习等）；老狗玩不了新把戏◆My grandmother doesn’t want a computer. She says you can’t teach an old dog new tricks. 我奶奶不想要计算机，她说人老不学艺。●can/could teach/tell sb a ˈthing or two (about sb/sth) (informal) be able to help sb, or teach sb how to do sth, because you have more experience（因为有更多经验而）能帮点忙，能教某人一些东西◆He thinks he knows a lot about farming, but old Bert could teach him a thing or two.他以为自己对种田所知甚多，但是老伯特会给他上点课的。