– May I go to the movies tonight mum? You can when you your homework.A. will finishB.

问题补充：

– May I go to the movies tonight, mum?

-- You can when you your homework.

A. will finish

B. are finishing

C. will have finished

D. have finished

答案：

A. will finish

B. are finishing

C. will have finished

(答案→)D. have finished

解析：考查时态。句意：妈妈，今晚我可以去看电影吗？当你完成你的作业的时候你可以去。A表示将来B表示的是正在完成，C将来完成时指到将来的某个时间为止，D用完成时态表示对现在造成影响或结果。根据句意完成作业的时候可以去看电影，造成了一定的影响，所以选D。