1 . Only when we saw the photos about the air crash_____ how terrible it was.

A．had we known

B．we had known

C．did we know

D．we knew

2 . The project he had devoted himself ______ a perfect success.

A．to proved

B．proved

C．to prove

D．to proving

3 . The other day, we brought along pieces of old bread and__________(feed) the birds. (所给词的适当形式填空)

4 . Slowly, and with the camera still held to my eye, I turned... and __________ (freeze). (所给词的适当形式填空)

5 . It suddenly ________ (occur) to him that he had an important meeting to attend the next morning. (所给词的适当形式填空)

6 . Talented in both medicine and sports, Robin ________(tear) between becoming a doctor and an athlete when he graduated. (所给词的适当形式填空)

7 . In his 30s, he c_________ (投入) a lot of time to reading newspapers in the morning. (根据中英文提示填空)

9 . The black car drove away from them and ____________(消失). (根据汉语提示单词拼写)

10 . Had I known the party was so boring, I wouldn’t have come. It __________ (prove) a failure. (所给词的适当形式填空)