第二部分 英语知识运用（共两节满分45分）
第一节 单项填空 （共15小题；每小题1分，满分15分）
从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
例：We _______ last night, but we went to the concert instead.
A. must have studied B. might study
C. should have studied D. would study
答案是C。
21 --In recent years, ________ problem of global warming has become very serious.
--That’s right. People are facing ________ number of natural disasters now.
A. the; a B. a; the C. a; a D. the; the
22. A terrible earthquake struck Ya’an in Sichuan Province, ________ a lot of deaths and damage.
A. caused B. causing C. having caused D. to cause
23. The factory used 65 percent of the raw materials, the rest of which ______ saved for other purposes.
