A. answer
B. answering
C. to answer
D. answered

A. Know 
B. Knowing
C. To know
D. Known

A. to see
B. sees
C. seeing
D. see

1. He has no time ________ (去踢球).
2. I'm looking for a house ________ (住).
3. Kate wants a pen ________ (写).
4. It's not difficult for him ________ (学英语).
5. He wanted ________ (成为) an inventor.
6. I don't know ________ (去哪儿).
7. It took me half an hour ________ (做家庭作业) yesterday evening.
8. My teacher often hears Tom ________ (讲话) in his class.
9. It's raining heavily. You'd better ________ (待在家里).
10. Jim is the first one ________ (到) to school every day.

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

1. He hopes that he will be back very soon.
    He hopes _______ _______ back very soon.
2. Could you tell me how I can get to the post office?
    Could you tell me ________ ________ to the post office?
3. The boy didn't know what he should do with the broken glass.
    The boy didn't know ________ ________ do with the broken glass.
4. The girl found there was a wallet lying on the ground.
     The girl found a wallet ________ on the ground.
5. I take back what I said. 
    I take back ________ ________.
6. I remember that I have told her the truth.
    I remember ________ ________ the truth.
7. I decided that I would visit Mr. Black.
    I decided ________ ________ Mr. Black.
8. I don't know what I should do next.
    I don't know ________ ________ do next.
9. We saw that they swam just now.
    We saw _______ ________  just now.
10. It seems that he knew me. 
      He seems ________ ________ me.

A. to see
B. see
C. to seeing
D. seeing

1. To eat a balanced diet is very important.
    _____ very important _____ eat a balanced diet.
2. They are watching TV at home now.
    They are watching TV at home _____.
3. What's wrong with your sister?
    What's_____ _____ with your sister?
4. She has a sore throat.
    There is something _____ _____ her throat.
5. There is a lot of milk in the bottle.
    There is _____  _____ milk in the bottle.

A. eat
B. to eat
C. eating
D. eats

A. to learn; to speak
B. learning; speaking　?
C. to learn; speaking
D. learning; to speak?