:Ⅴ. 单项选择(每小题1分， 共15分)
从A、B、C、D四个选项中选择可以填入空白处的最佳答案。
( )21. Every farmer knows that weather plays a part _______ farming.
A. at B. in
C. to D. of
( )22. To keep healthy, you should eat _______ junk food and do more exercise.
A. little B. few
C. less D. fewer
( )23. —It’s difficult for Bill to make a plan in _______ a short time.
—You’re wrong. He is clever enough to do it.
A. too B. enough
C. so D. such
( )24. To have a good living environment, we should do everything possible to fight _______.
A. education B. competitions
C. pollution D. discussions
