20．I _______ the dance performance many times, each giving me a new understanding．

　　　 A．watch　　　　　　　 B．watched　　　　　 C．have watched　 D．am watching

19．The economic impact study was conducted by a group of _______ selected MBA students at the University of Kansas．

　　　 A．especially 　　　 B．specially　 　　　　 C．regularly　 　　　 D．potentially

18．_______ any other species, human populations are shaped by the usual forces of natural selection, like famine, disease or climate．

　　　 A．Compared with　 B．As with　 　　 C．As for 　　　　　　　 D．In addition to

17．- I’m terribly sorry to keep you waiting for so long．

　 - _______．

　　　 A．Never mind．　 B．That’s right．　　 C．You are welcome．　 D．Don’t mention it．

16．It’s extremely dangerous for the drivers to _______ speed as the traffic lights are changing．

　　　 A．pull up　　　　　　　 B．put up　　　　　　　 C．rise up　　　　　　　 D．pick up

15．The government is now trying to provide _______ health benefits to all citizens in China．

　　　 A．significant　　　　 B．universal　　　　　 C．temporary　　　　 D．professional

14．With more than 17000 islands, _____ only 6000 are inhabited, Indonesia is the world’s largest archipelago (岛国)．

　　　 A．on which　　　　　 B．for which　　　　　 C．of which　　　　　 D．along which

13．- Where will you start your work after graduation？

　 - It’s not been decided yet．I _______ continue my studies for a higher degree．

　　　 A．need　　 　　　　　 B．might　　 　　　　　 C．would 　　　　　　 D．must