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)
请认真阅读下面各题，从题中所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
21. — What ______ fun it was to look around the Slender West Lake last week !
— Yeah. It was quite ______ unforgettable experience.
A. a; 不填 B. 不填; an C. a; an D. 不填；不填
22. The top student named Michael in my class could have finished the English paper on schedule, but __________ she failed.
A. however B. somewhat C. anyhow D. somehow
23. — Nancy doesn’t look very well. What’s wrong with her?
—She has a terrible headache because she ____ too long. She should stop to have a good rest.
A. has been writing B. had written C. is writing D. was writing
24. —David has made great progress recently.
—________，and ________.
