Mark was a student at this university from 1999 to 2003, he studied very hard and was made Chairman of the Students Union.
A. during which time
B. for which time
C. during whose time
D. by that time
网友回答
(答案→)A. during which time
B. for which time
C. during whose time
D. by that time
解析：此题考查非限制性定语从句。首先排除D项，因为它构不成定语从句；was made chairman为短暂动作，不能加for引导的一段时间，因此，排除B项；C项关系代词“whose” 应用错误，1999 to 2003并不为Mark独有。故应选择A项。全句意为:马克从1999年到2003年在上大学，在这几年期间他学习刻苦，被选为学生会主席。