26. Walking does need a bit of practice _____ gravity has changed.

　 A. as if　 B. in their turn　 C. now that　 D. as a result of

25. They multiplied and filled the oceans and seas with oxygen, _____ encouraged the later development of early shellfish and all sorts of fish.

　 A. that　 B. where　 C. when　 D. which

24. _____ is even more important is that as the earth cooled down, water began to appear on its surface.

　 A. As　 B. That　 C. What　 D. Where

23. It was not immediately obvious _____ water was to be fundamental to the development of life.

　 A. what　 B. that　 C. when　 D. why

22. --- I wonder if I could possibly use your car for tonight?

　 ---______. I'm not using it anyhow.

A. Sure, go head　 B. I don't know　 C. Yes, indeed　 D. I don't care

第一节　 单项填空(共15小题；每小题1分，共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。

21. .--- Excuse me, can you tell me where the nearest bank is, please?

　 ---______ Oh yes! It's past the office, next to a big market.

A. Mm, let me think.　　　　 B. Oh, I beg your pardon?

C. You're welcome.　　　　　 D. What do you mean?

20. 在中，分别是角A,B,C的对边，且,

　 (1)求的面积　　

(2)若，求角C.

附加题:已知都是正数，满足，求的最大值，并求出此时的值。

19. 等比数列 中，已知，

(1)求数列 的通项公式；

(2) 若和分别是等差数列的第三项和第五项，试求数列的通项公式及前项和.