问题补充:
You will have to wait for one more week, the manager will be back from his trip.
A. after
B. while
C. when
D. since
答案:
A. after
B. while
(答案→)C. when
D. since
解析:when引导的非限定性定语从句,本句中的when = by which time,“到那时候”。after和since都错在时间的先后顺序,而while引导时间状语从句不用将来时。