问题补充:
Mary gave Jack so much help that he gave her some roses for her kindness
A. in turn
B. by turns
C. in answer
D. in return
答案:
A. in turn
B. by turns
C. in answer
(答案→)D. in return
解析:句意:Mary给了Jack很多帮助,所以作为她善良的回报,Jack送给Mary一些玫瑰花。in turn依次;by turns轮流地;in answer回答;in return作为回报,选D。