二、单项选择（共15小题；每小题１分，计15分）
在下列各题A、B、C、D四个选项中选择一个能填入题干空白处的最佳答案。
21. -- How about ______car exhibition? -- I should say it was ______ success.
A. the, a B. the, / C. a, a D. a,/
22. — Can I see the headmaster at the moment, please?
—I’m afraid not. He ______________out. He ___________in 10 minutes.
A. goes; comes B. has gone; comes
C. will go; will come D. has gone; will come back
