Ⅱ. 单项填空(共15小题;每小题1分, 满分15分)
21. They claimed that_____1, 000 factories closed down during the economic crisis.
A. properly B. approximately
C. independently D. considerably
【解析】选B。考查副词词义辨析。句意:他们声称在经济危机期间大约有1 000家工厂倒闭了。properly合适地,恰当地;approximately大约,近似地;independently独立地;considerably大量地,根据句意选B。