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 I am used to getting up before dawn ______ it is still dark outside.

A. though              B. but                 C. which        D. when

 ---Shall I lock the lab now before I go home?

---______. I’ll check it myself later.

A. Go ahead           B. No problem                     C. No hurry           D. Don’t bother    

 This is a city which lives for today while ______ by its past.

A. surround           B. surrounding              C. surrounded        D. to surround

 Flowers growing in a well-equipped greenhouse find ______ hard to survive in the wild.

A. it                      B. that              C. so               D. very

 The magnificent tower must be saved, ______ the cost!

A. however            B. whichever           C. whatever         D. wherever

 The students will usually have a very anxious time ______ for the results of college entrance

examinations.

A. wait                  B. waited              C. to wait                  D. waiting

 It ______ sound like a perfect destination, but it is really adventurous to go there.

A. should               B. must               C. shall            D. may

 After two years' careful study, we now have a ______ better understanding of the cause of the

problem.

A. very          B. much                            C. fairly           D. quite

Students should often be allowed to work in groups, ______ gives them chances to co-operate and to share.

A. who　　　　 B. where　　 　　　 C. which　　 　　　　　 D. what

 To help myself get to sleep, I have tried several ways but it seems that ______ works.

A. no            B. none             C. neither                 D. all