问题补充：
--Could you tell me ?
--Next week.
A. when John will come back
B. when will John come back
C. when John came back
D. when did John come back
答案：
(答案→)A. when John will come back
B. when will John come back
C. when John came back
D. when did John come back
解析：宾语从句中一般为陈述句语序，选项A问的是约翰什么时候回来，将来时态。选项C问的是约翰什么时候回来的，过去时态。根据答语下周，表示将来时态的时间状语，选A.
