41,cost somebody an arm and a leg

　　A: Did you see the diamond ring Bill gave to Linda?

　　B: I sure did. It must have cost him an arm and a leg.

　　42, cut it out 闭嘴

　　I told you to cut it out.

　　43,be cut out for 生来时做……的

　　Dr. Hamilton doesn’t feel Larry is cut out for the medical profession.

　　44,department chair 系主任

　　I didn’t write that memo to the department chair.

　　45,dirt cheap 非常便宜

　　A: You’ve already furnished your apartment?

　　B: I’ve found some used furniture that was dirt cheap.

　　46, do with 用…..凑合; do without 没有……也行

　　You can do with your girlfriend.

　　You can do without your girlfriend

　　47, dog tired 特别累，同义：run down; worn out; out of steam

　　I’m dog tired these days. I’m working on seven articles.

　　48, down jacket 羽绒服

　　49，drive somebody up the wall 让某人发疯；同义：drive somebody out of one’s mind

　　The sound of all that raffic is driving me out of my mind.

　　50, fall back on 依赖

　　A: Were you able to understand that French novel without any help from theteacher?

　　B: I did pretty well, but I had to fall back on my dictionary occasionally.