17. vague　含糊的，不明确的　a vague answer　　 a vague idea

Don’t you have the vaguest idea where you have left the key.

16. the summer vacation 暑假　be on vacation =be on leave = be on holiday 在度假中

15. used to do sth　 There used to be a cinema.　 be used to doing 　　be used to do sth　　 Water is used to produce electricity.　　 a used car　 用过了的

14. use 使用　 be in use　 be out of use　 use up　用光

be of use = be useful　　 make use of　 Every possible use has been made of his spare time.

13. urge　 催促，鼓动　 urge sb to do

12. upset　 使心烦意乱，弄翻，打乱　 upset sb, upset a cup, upset the balance of nature

11. What’s up?　 出了什么事　 It is up to you to decide.　 由你来决定

up and down　 go up　　 end up with sth　 end up by doing sth　 put up　 shut up

10. not…until　 直到…才　 He didn’t stop working until his mother came back.

Not until his mother came did he stop working,

It was not until his mother came back that he stopped working.

9. universal　 普遍的，全世界的　 topics of universal interest　　 a universal truth　 普遍真理

8. The problem is by no means unique to this region.　个问题决不是这个地区特有的