We finally managed to _____ the committee's approval of our plans.
| A．secure | B．arouse | C．acquire | D．exert |
I thought things would get better, but it is they are getting worse.
| A．before | B．because | C．as | D．after |
Although he knew little about the large amount of work done in the field , he succeeded other more well-informed experimenters failed.
| A．as | B．unless | C．what | D．where |
John waited at the bus-stop for nearly half an hour the bus finally arrived .
| A．when | B．as | C．before | D．while |
Not that I’m unwilling to lend you a hand ,I’m too busy for the moment .
| A．because | B．but that | C．but | D．however |
Jack had traveled six miles across the Channel _____his engine failed and was forced to land on the sea .
| A．when | B．until | C．after | D．since |