问题补充:
You can certainly leave the classroom as soon as your homework.
A. has done
B. has been done
C. will be done
D. will have been done
答案:
A. has done
(答案→)B. has been done
C. will be done
D. will have been done
解析:在时间状语从句中可以用现在完成时表示将来,强调从句的动作发生在主句谓语所表示动作之前。