问题
选择题
— The window must have taken you quite a lot of time that day.
— You are right. They _____ for weeks.
[ ]
A. haven't been cleaned
B. hadn't been cleaned
C. didn't' clean
D. haven't cleaned
答案
答案:B
— The window must have taken you quite a lot of time that day.
— You are right. They _____ for weeks.
[ ]
A. haven't been cleaned
B. hadn't been cleaned
C. didn't' clean
D. haven't cleaned
答案:B