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. — When did Christina find her purse missing?
— It was not until she arrived at the shopping mall ________ she got ready to buy her mother a gift.
A. before B. that C. where D. why
22. I’d like to be rewarded with a smile from our teacher ________ I finish presenting my research result.
A. hardly B. quickly C. constantly D. immediately
23. The manager has decided to put ________ he thinks is energetic and clever in the position of the leadership of the company.
A. whoever B. anyone C. whomever D. those
24. China’s first aircraft carrier, ________ as long as 304 metres, was handed over to the People’s Liberation Army navy in 2012.
A. measures B. measuring C. to measure D. measured
