1 . The students_____heatly when the teacher came in.

A．discussed

B．had discussed

C．would discuss

D．were discussing

3 . It took 500 workers 100 days to build the fine model，________ the thousands of props inside. （根据句意填空）

4 . I shall never forget those years _______ I lived in the country with the farmers, _______ has a great effect on my life

A．that; which

B．when; which

C．when; who

D．which; that

5 . ______Yang did not get the best scores on every single test, it was his high scores on the psychological tests that finally won him the status of China’s first astronaut.(所给词的适当形式填空)

6 . Recently I________(see) an unusual number of UFOs! （所给词的适当形式填空）

7 . If________(breathe)in, the viruses can result in illness or even death.（所给词的适当形式填空）

8 . 警察加强了对三天前失踪的那个男孩的搜寻工作。
The police have stepped ____________ their search for the boy ____________ went missing three days ago.

9 . 柯林和我打算在他上大学之前花几个星期去旅游。
Colin and I plan to spend a few weeks ____________ before he ____________ to university.

10 . 我妈妈总是叫我不要和别人打架。
My mother ____________ telling me not ____________ fight with others.