1 . Wilhenlm Roentgen was a German scientist. In 1895 he was doing an experiment __________ he discovered X-rays by accident. (用适当的词填空)

2 . It was the third time that I _________ (bite), so I went to the hospital a third time. （所给词的适当形式填空）

3 . It was not until we suffered a lot from the loss of a balanced environment _______ we realized the importance of protecting wildlife. (用适当的词填空)

4 . I’d appreciate ___________ if you keep silent. (用适当的词填空)

5 . It is no good ____________ (cry) over split milk. (所给词的适当形式填空)

6 . Rather than go home, he always prefers to w________(徘徊) on the street when his parents quarrel. (根据中英文提示单词拼写)

7 . The other day, ________ occurred to Johnson that he should make a road trip to help the needy. (用适当的词填空)

8 . We were about to head for the next tourist attraction _________ it began to rain.(用适当的词填空)

9 . I would appreciate ________ if you could keep silent. (用适当的词填空)

10 . My father prefers________movies at a cinema rather than________the internet.

A．to watch, surfing

B．to watch, to surf

C．watching, surf

D．to watch, surf