| — 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 |
| — 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 |