第二部分：英语知识运用（共两节，满分45分）
第一节：语法和词汇知识（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。
21. The best way to explore _______ countryside is on _______foot.
A. a; a B. 不填; the C. a; 不填 D. the; 不填
22. Mike has recently caught A-H1N1. ________, he will have to be away from school for several days.
A. In other words B. After all C. As a result D. As well
