第一节：单项填空（共15小题；每小题1分，满分15分）
从每题所给的A、B、C、D四个选项中，选出可以填入空白处的最佳选项。
21．Shanghai celebrated one year countdown (倒计时) to the opening of____ 2010 World Expo on May 1, 2009.
A. the ;/ B. a; the C. the; the D. an; the
22．Use your head. nothing taught by others can have the same effect on you as ________learned by yourself．
A. those B. what C. that D. the one
