【题目】--- What do you think of Peter?
--- He is a helpful man. He is always helping others without expecting anything .
A. in turn B. in need
C. in return D. in vain
在线课程【答案】C
【解析】考查词组。A. in turn 反过来，轮流； B. in need需要；C. in return得到回报；D. in vain徒劳。上句：你觉得彼得怎么样？下句：他是一个乐于助人的人，他总是不求回报地帮助别人。故选C。