27. A mysterious illness, referred to as “ a typical phenomena”, has been brought under control, the government said on Wednesday, ______ no cause of it has been made public.

A. though　　　 B. when　　　　 C. that　　　　 D. because

解析：“尽管”没有病例公布

26. Before leaving home, make sure to turn off the electricity, lock the door, ______ the windows open.

A. and not to leave　　　 B. instead of leaving　　　 C. rather than leave　　 D. and not leave

解析：lock和 turn都是不定式肯定形式lock 前省略了to ,但not to leave 是否定形式，to不可省

25. I can _____ some noise while I’m studying, but I can’t stand very loud noise.

　 A. put up with　　　 B. get rid of　　　 C. have effects on　　 D. keep away from

解析：从后面的stand可以推断，这里用put up with 表示忍受

24. How many of us ______ a meeting that is not important to us would be interested in the discussion?

A. attended　　　 B. attending　　　 C. to attend　　　 D. have attended

解析：attending a meeting that is not important to us做定语

23. The idea for the new machine came to Mr. Baker ______ to his invention recently.

　 A. while devoting　 B. while devoted　 C. while he was devoted　 D. while devoting himself.

解析：while后主语及助动词不能省略，因为两句主语不一致

　 Mr Baker thought of the idea for the new machine　 (B / D)　 to his invention recently.

22. Professor Liu has ________ teach psychology since he came to the Central China Normal University.

　 A. determination to B. been determined to　 C. been determining to D. determined to

解析：Since引导的时间状语从句强调主句谓语动词动作的持续性。

21. ----Any news about Bill Clinton?

　 ----He left power three years ago and has a little now and a little then been ______.

　 A. heard of since　　 B. heard since　　 C. heard before　　 D. heard of before

解析：答句可改为I have heard of him a little now and a little then since he left power three years ago.→

　　　　 He has a little now and a little then heard of since he left power three years ago.

20. If you want to sell your product you must _____ it.

　 A. advertise　　 B. advertise for　　 C. advertise on　　 D. advertise to

解析：advertise sth. 为……登广告， 登广告宣传……　 advertise for sth.(sb.)登广告征求或寻找某物或某人

　 比较：advertise jobs 登广告招人　　　 advertise for jobs　 登广告求职

19. Are the parents who let their child who is ______ walk in the dark alone at night considerate?

　 A. young enough　 　 B. too young to　　　 C. not old enough to　　　　 D. so young

解析：分析句子结构，who is so young 在句为修饰的定语,另有let sb.do sth.

18. ________ doesn’t seem to have been much difficulty in solving the problem.

　 A. It　　　 B. That　　　 C. There　　　 D. He

解析：这是There be句型一种比较复杂的表现形式，由下列各句逐步形成：

　There is much difficulty in solving the problem.

　There seems to be much difficulty in solving the problem.

　There seems to have been much difficulty in solving the problem.

　There doesn’t seem to have been much difficulty in solving the problem.

E.g. There used to be a big tree in front of the old house.

There happened to be a foreign teacher there.

There is said to be no life on the moon.

There must have been something wrong with the machine.