___ the temperature falling rapidly, we couldn’t go on with the experiment.
| A．Since | B．For | C．As | D．With |
—Does John serve in the army?
—No, but he________in the army for 8 years.
| A．would serve | B．has served | C．is serving | D．served |
He was working on a new book ________ I went to see him.
| A．first time | B．for the first time |
| C．by the first time | D．the first time |
Not until the motorbike looked almost new repairing and cleaning it.
| A．he stopped | B．did he stop |
| C．stopped he | D．he did stop |
---I’m going to San Francisco for a couple of days
---_________.I wish I could get away for a while.
| A．It doesn’t matter. | B．Forget it. |
| C．I really envy you. | D．I can’t agree more. |
It's no good ________ here. Let's go home.
| A．to wait | B．waited | C．waiting | D．being waited |