第一节 单项填空（共15小题；每题1分，满分15分）
从（A、B、C和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.---Shall we open the window to let some fresh air in?
---_________. I’m feeling a little cold.
A. No, I would rather not. B. Sure, go ahead please.
C. Sorry, you’d better not. D. Yes, that couldn’t be better.
22. You are well prepared for the job interview, ______ there’s no need for you to get so nervous.
A. or B.while C.but D. so
23. In the rice-growing world, ______ Chinese scientist, Yuan Longping, is ______ leading figure.
A. a; the B.the; a C.a; a D. the; the
