A. visiting his daughter

    B. to visit his daughter

    C. visit his daughter

    D. visited his daughter

    22. Are you serious in ____ such a view？

    A. putting on

    B. putting off

    C. putting up

    D. putting forward

    23. The plane crashed，its bombs ____ as it hit the ground.

    A. exploded

    B. were exploded

    C. exploding

    D. were exploding

    24. You should be content            what you have.

    A. to

    B. about

    C. with

    D. for

    25. “Do you like to ride on the old bus to school？” Yes，I prefer it _____.

    A. to walk

    B. to walking

    C. walking

    D. having walked

    26. My vacation begins next Tuesday，____ I will leave for Florida.

    A. which

    B. that

    C. while

    D. when

    27. Can you tell me ____ about the city that makes people love it so much？

    A. it is what

    B. what it is

    C. what is it

    D. is it what

    28. Though he is very intelligent，he is ____ rather modest.

    A. hence

    B. otherwise

    C. nevertheless

    D. therefore

    29. Lack of imagination is an obstacle ____ one's advancement.

    A. to

    B. of

    C. for

    D. about

    30. If you can provide the wine，I'll ____ the food.

    A. see to

    B. look at

    C. ask for

    D. think about

    参考答案：

    21.D 22.D 23.C 24.C 25.B 26.D 27.B 28.C 29.A 30.A