21. The population of Jiangsu __ to more than twice what it was in 1949. The figure is now approaching 74 million.
A. has grown B. have grown C. grew D. are growing
【答案】A
【解析】考察主谓一致和时态。population是集合名词，或集体名词，即看成一个整体，所以谓语动词用单数形式。句子说的是江苏现在的人口数量和以及增长，用完成时表示现在的状态。
22. -- Ann is in hospital.
-- Oh, really? I __ know. I __ go and visit her.
A. didn’t; am going to B. don’t; would
C. don’t; will D. didn't; will
【答案】D
【解析】考查时态和交际用语说话者用I _didn't_ know，是表示现在之前他不知道。而他现在说要去看他当然是将要去看他用“will'.
23. Because of the financial crisis, days are gone _ _ local 5-star hotels charged 6,000 yuan for one night.
A. if B. when C. which D. since
【答案】B
