Both the Winter and Summer Olympics are held ___________on a regular basis.
| A．every four years | B．four years |
| C．for four years | D．every fourth year |
Was it not until you began to work ______ how much time you had wasted?
| A．did you realize | B．that you realized |
| C．did you not realize | D．that you didn’t realize |
A man does not know the difficulty of anything_________ he does it personally.
| A．although | B．if | C．because | D．unless |
I caught the last bus from town, but Harry came home___________ that night.
| A．very late | B．even later | C．the same late | D．the last one |
Mrs. Green wants to buy that kind of cloth because she___________ that the cloth__________ very well.
| A．has been told; washes | B．is told; is washed |
| C．has been told; is washed | D．is told; is washed |
_______ Tom, we wouldn’t have been late for the last bus.
| A．If we didn’t wait for | B．If we haven’t waited for |
| C．we hadn’t waited for | D．Had we not waited for |