6．Having checked the doors were closed and ________ all the lights were off，the boy opened the door to his bedroom.

A．why B．that C．when D．where

答案　B

解析　句意为：这个男孩在检查完门都关了，所有的灯也都关了以后，才打开自己的卧室门。动词checked后接两个宾语从句，第一个宾语从句为"the doors were closed"；第二个宾语从句为"all the lights were off"，其前的that不能省略。

7．To improve the quality of our products，we asked for suggestions________had used the products.

A．whoever B．who

C．whichever D．which

解析　句意为：为了提高我们的产品质量，我们向任何使用过我们产品的人征求意见。asked的宾语已经后置，即whoever had used the products，其中whoever可以分解为anyone who。

8．-Why not buy a second­hand car first if you don't have enough money for a new one?

-That's a good________.

A．saying B．question

C．suggestion D．account

答案　C

解析　考查名词词义辨析。句意为：--如果你的钱不够买辆新车，你为什么不先买辆二手车呢？--那是个好建议。suggestion建议，提议，符合句意。saying谚语，格言；question问题；account陈述，报告，账户。

9．The biggest surprise for John was ________ he was chosen as team captain.

A．when B．what

C．which D．whether

答案　A

解析　句意为：对约翰来说最大的惊喜是他被选为队长的时候。when引导表语从句，表示"......的时候"。

10．Some researchers believe that there is no doubt ________a cure for AIDS will be found.

A．which B．that

C．what D．whether

答案　B