The trees must ________ three times a week.

A. water

B. is watering

C. be watered

D. waters

?I saw Betty go to Grandpa Zhang's home just now.　　

?Yes, she is often seen ________ the old man with his housework.

A. help

B. to help

C. helps

D. helped

I like my new bike. It ________ very well.

A. rides

B. is riding

C. is ridden

D. has ridden

Mr Johnson's story ________ by everyone who heard it.

A. laughed at

B. was laughed

C. laughed

D. was laughed at

A talk on science ________ in our school next Monday.

A. will give

B. will be given

C. has given

D. has been given

Mm, the tea smells nice. Where is it ________ ?

A. built

B. tried

C. done

D. produced

The PLA ________ in 1927.

A. was found

B. found

C. was founded

D. founded

I'm sorry you can't go in now. The room ________ yet.

A. hasn't been cleaned

B. hasn't cleaned

C. isn't been cleaned

D. isn't being cleaned

?Will you come to the dinner party?

?I won't come unless Jenny ________.

A. will be invited

B. can be invited

C. invited

D. is invited

We ________ not to play computer games.

A. are told

B. have told

C. told

D. tell