第二部分 英语知识运用（共两节，满分45分）
第一节 单选填空（共15 小题；每小题1分，满分15分）
从A、Ｂ、Ｃ、Ｄ四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该选项涂黑。
21. On Friday ________ President Obama and his wife hosted ________ White House dinner with the visiting British guests.
A. 不填; a B. the; the C. 不填; the D. the; a
22. Why does your brother ______ a sad look on his face these days?
A. bring B. wear C. show D. hold
23. The new system needs to be in operation for five months _______ it can be updated.
A. as B. while C. before D. once
24. Energy, passion and a burning desire are, you see, _______ true learning takes.
A. that B. what C. how D. which
25. — You look great! Were you on vacation or _______?
— You got it. I’ve just come back from America.
A. anything B. nothing C. everything D. something
