YangLiweiwasastudentatthisflightschoolfrom1983to1987,

Yang Liwei was a student at this flight school from 1983 to 1987, he studied very hard and was made chairman of the Students’ Union.A.during which timeB.for which timeC.during whose timeD.by that time

A解析试题分析：考查定语从句，介词+which的用法，先行词是from 1983 to 1987,，说明是在那段时间，用during，which指from 1983 to 1987，句意是：杨利伟在1983到1987年在这个飞行学校做学生，在这段时间他学习努力，当选学生会的主席。选A。
考点：考查定语从句
点评：考查定语从句要看先行词和分析定语从句的成分，要是介词的选择可以从先行词或定语从句的动词搭配。

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