Many people believe we are heading for environmental disaster _____we radically(彻底地) change the way we live.
| A．but | B．although | C．unless | D．until |
I had expected to come over to see you last night, but someone ______ and I couldn’t get away.
| A．called | B．had called |
| C．would call | D．would have called |
We had wanted to come to see him, but we ____ no time.
| A．had | B．had had |
| C．would have | D．would have had |
We had hoped that you would be able to visit us, but you _____.
| A．didn’t | B．hadn’t |
| C．needn’t | D．would not have |
We had hoped to catch the 10：20 train, but _____ it was gone.
| A．found | B．had found |
| C．would find | D．would have found |
— Oh, I ______ where he lives.
— Don’t you carry your address book？
No, I ______ to bring it.
| A．forget, forget | B．forgot, forgot |
| C．forget, forgot | D．forgot, forget |