2、作状语：We have breakfast at seven.(表时间)；They were late for meeting because of the heavy rain.(表原因)；They started the machine by pressing the button.(表方法)

介词又叫前置词，是一种虚词。介词分为三种，一种是简单介词，如at, in, on, beside, to , for等；另一种是短语介词，即由两个以上的词组组成的短语，如in front of, because of, out of, instead of等；还有一种叫二重介词，如until after, from behind等。

(一)介词的句法功能

介词不能独立在句中做成份，介词后必须与名词、代词、或动名词构成介词短语在句中充当一个成份，表示人、物、事件等与其它人、物、事件等之间的关系。

1、作定语：The book on the table is mine.

24．(浙江卷)15. We always keep ________ spare paper, in case we ran out.

A. too much 　 B. a number of　　 　　 C. plenty of　 　 D. a good many

Keys: 1-10 CDCAA ACAAD 11-20 ABCCB BACAB 21-24 BCCC

23．(广东卷)28. Much of the power of the trade unions has been lost 　　　　　, their political influence should be very great.

　　 A. As a result　　　　　 B. As usual　　　　　　　 C. Even so　　　　 D. So far

22．(全国卷2)14. -Did you take enough money with you?

-No, I needed _______ I thought I would.

A. not so much as B. as much as　 C. much more than　 　 D. much less than

21．(江西卷)35．I don't think this film is by far the most boring. I have seen_________.

A. better　　 B．worse　　 C．the best　　 D．the worst

20．(上海春)31. 　　 Some experts think that language learning is much ___ for children as their tongues are more flexible.

A. easy 　　　　 B. easier 　　　　　 C. easily 　　　　　 D. more easily

19．(北京卷)21. This washing machine is environmentally friendly because it uses _____ water and electricity than _____ models.

　 A. less ; older　 B. less ; elder C. fewer ; older　　 D. fewer ; elder

18．(浙江卷)12. Progress so far has been very good. _______, we are sure that the project will be completed on time.

　 A. However　 B. Otherwise　　 C. Therefore　　 D. Besides

17．(浙江卷)9. _________ by keeping down costs will Power Data hold its advantage over other companies.

　 A. Only　 B. Just C. Still　　 D. Yet