21. I believe it is one of the best books _______ written on the subject.

　　A. that have ever been B. which have ever been

　　C. that has ever been D. which has ever been

　　22. This is a very _______ issue and we haven’t figured out a way to deal with it yet.

　　A. competent B. compound C. comprehensive D. complicated

　　23. Mary helped Bill whenever he was in trouble but he never did anything for her _______.

　　A. in turn B. in advance C. in return D. in vain

　　24. Can you tell the _______ difference between the two words?

　　A. slender B. single D. slight D. simple

　　25. The _______ of the movie is so great that many people want to see it.

　　A. attack B. attraction C. attempt D. attention

　　26. The old man, _______ poor, could not afford a decent meal.

　　A. being B. is C. was D. has been

　　27. Our sportsman won the race ______ at the Olympics.

　　A. with easiness B. in ease C. with ease D. at ease

　　28. They strongly recommended that you _______ the area sooner.

　　A. leave B. left C. leaving D. to leave

　　29. What I can see is there will be many people ________ to visit the place.

　　A. coming B. come C. came D. to come

　　30. We need a chairman _______.

　　A. for whom everyone has confidence

　　B. who everyone has confidence of

　　C. in whom everyone has confidence

　　D. whom everyone has confidence on

答案：
21-25 ADCCB
26-30 ACAAC