29. You can’t imagine what difficulty we had ____　 home in the snowstorm.

　 A. walked　 B. walk　 C. to walk　 D. walking

28. When asked why he went there, he said he was sent there ____ for a space flight.

A. training　 B. being trained　 C. to have trained　 D. to be trained

27. ______ their hats into the air, the fans of the winning team let out loud shouts of victory.

　 A. To throw　 B. Thrown　 C. Throwing　 D. Being thrown

26. They desired that they _____ the right to vote.

　 A. had　　 B. have　　 C. are　 D. were

25. As the boy listened attentively in class, everything his teacher said was easily______.

　 A. for him to understand　 B. understood　 C. to understand　 D. to be understood　

24. Mary is said _____ in the supermarket for 5 years, but I don’t know why she resigned last month.

A. to have been working　　 B. work　 C. to be working　 D. to have worked

23. ______ from the space, you will find the earth is blue.

　 A. Seen　 B. Seeing　 C. See　　 D. To see

22. He was about to go out for a walk _____ his teacher came to visit him.

　 A. while　　 B. which　 C. when　 D. then

从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。

21. I will never forget ____ to country village to see the poor children of my age.

　 A. to take　 B. to be taken　　 C. taking　 D. being taken