重点讲解：
1. set back 使花费；使破费；
In 1981 dinner for two in New York would set you back ￡5.
1981 年的时候,在纽约两个人吃一顿饭要花费 5 英镑~~ps~#K[,F。
2. come down (成本、水平或数量)下降，降低；
Interest rates should come down.
利率应该降低B%qTH%m3JR^(X,Ya&6[U。
3. succeed in sth./doing sth. 达到目的；成功做成；办到；
Some people will succeed in their efforts to stop smoking.
一些人经过努力可以成功戒烟kCWq|XOljX_9!b。
4. on purpose 特意地；故意地；有意地；
Was it an accident or did David do it on purpose?
是意外还是戴维故意所为？