There were some chairs left over ________ everyone had sat down.
| A．when | B．until | C．that | D．where |
Do you know the year _____Einstein died?
| A．when | B．at which | C．for when | D．in when |
That is the reason _____I refused it.
| A．why | B．for that | C．because | D．which |
This is the factory _____my father worked ten years ago.
| A．where | B．that | C．which | D．for the which |
The conference has been held to discuss the effects of tourism ______the wildlife in the area.
A. inB onC. atD. with
Sorry, madam. You’d better come tomorrow because it’s _____the visiting hours.
| A．during | B．at | C．beyond | D．before |