22.　 Is this research center _____ you visited the modern equipment last year?

A. where　 　　　　 B. that　　 　　　　 C. the one that　 　　 D. the one where

21.　 Such good use has been _____ his spare time ____ his English has improved a lot.

A. made of; that 　　　 B. made of; as　 C. made in; that 　　　 D. found in; as

20.　 America was ______ was first called “India” by Columbus.

A. that　　 　　　　 B. where　　 　　　 C. what　　 　　　　　　　 D. the place

19.　 We played in the garden till sunset, ______ it began to rain.

A. when　　 　　　　　　　 B. after　　 　　　　 C. while　　 　　　 D. then

18.　 I listened to Dr. Johnson’s lecture about biology, but I failed to get its key. Here “key” means _________.

A. words　　 　　　 B. notes　　 　　　 C. messages　 　 D. points

17.　 ______ all over the hills and around the lake are wild flowers of different kinds.

A. To grow　 　　 B. Growing　 　 C. Grown　　 　　 D. Grow

16.　 I was advised to arrange for insurance ______ I needed medical treatment.

A. although　　 　 B. in case　　 　 C. so that　　 　　 D. if only

15.　 It was very kind of you to do the washing-up, but you _____ it.

A. mustn’t have done　　 　　　　　　 B. wouldn’t have done

C. mightn’t have done　　 　　　　　　 D. didn’t have to do

14.　 --- I enjoyed myself so much at your birthday party.

--- _________.

A. Oh, that’s kind of you　　　 　　 B. Congratulations

C. Oh, I’m glad to hear that　　 　　 D. It’s a pleasure

13.　 However, at times this balance in nature is _____, resulting in a number of possibly unforeseen effects.

A. troubled　　 B. puzzled　　 　 C. disturbed　　 　　　 D. mixed