31. The level of the river ___ 20 centimeters over the security line and ____must be taken to control the flood.

　 A. is measured; measures　　　　　　　 B. measures; measurement

　 C. measures; measures　　　　　　　　 D. is measured; measurement

30. Edison asked his father why the hens could hatch eggs ___he couldn’t.

　 A. as　　　 B. and　　　　 C. when　　　 D. while

29. The new suspension bridge ___by the end of last month.

　 A. has been designed　　 B. had been designed　 C. was designed　 D. would be designed

28. ---How often do you attend the evening classes?

　 ---_____, three times per week.

　 A. On the whole　 B. On average　 C. Little by little　 D. In all　

27. The sun was shining brightly, ____ everything there look more beautiful.

　 A. making　　　 B. to make　　 C. made　　 D. having made　

26. ---May I use your computer, Alex?

　 ---Sorry. Mine _____.

　 A. has repaired　　　 B. is being repaired　 C. has been repaired　 D. is repairing

25. The Smiths have moved to Miami, Florida, ____ they dreamed long of living in.

　 A. where　　　 B. in which　　　 C. which　　 D. that　

24. The poem is hard to understand. Can you make ___ of it?

　 A. idea　　　 B. knowledge　　　 C. sense　　 D. understanding

23. –You are Mr. Zhang, aren’t you?

　 --______.

　 A. Absolutely　　 B. Naturally　　 C. Normally　　　 D. Completely

22. I have ___all my papers but I still can’t find my notes.

　 A. looked through　 B. looked for　 C. looked after　 D. looked out