从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21. —Excuse me, where can I get application form?
—Go to Window 10 , please.
A． an; the B． an; 不填 C．不填；不填 D． the; the
22. Out of the crowded bus______, who was dressed in a black suit and waved to a pretty woman.
A. a tall man stepped B. stepped a tall man
C. did a tall man step D. did step a tall man
