第一节单项填空 (共15小题；每小题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。
21. She was very good ____ me when I was ill. She told me that doing exercise was good ____ my health.
A. to; for B. for; to C. at; to D. to; to
22. It is quite an informal gathering, you needn’t _____ for it.
A. dress up B. dress in C. have dressed up D. have dressed in
