第二部分、英语知识运用（共两节，满分35分）
第一节、 单项填空（共15小题；每小题1分，满分15分）
从A、B、C、D 四个选项中，选出可填入空白处的最佳选项。
21.__________ has been announced, we shall have our final exam next month.
A. As B. It C. That D. What
22.It showed me that the way of education in Canada is quite different from __________ in China.
A. it B. one C. that D. this
