1 . We should protect the environment. We should not cut down the trees. (两句合一句)
We should protect the environment by ________ ________ down the trees.

2 . Thank you for ________ me to your birthday party yesterday.

A．invitation

B．invite

C．invited

D．inviting

3 . You should avoid ________ on the underground. It’s impolite and also against the rules.

A．eat

B．eating

C．ate

D．to eat

4 . Lin Chao is keen on ________ volleyball and practises hard.

A．to play

B．played

C．playing

D．will play

5 . Both of the twin boys denied ________ the windows of the living room.

A．break

B．broke

C．to break

D．breaking

6 . There is a big sale in the supermarket. What about ________ tomorrow?

A．go shopping

B．to go shopping

C．going shopping

D．went shopping

7 . After sending those e-mails, John started ________ the Internet for clothes.

A．surfing

B．surf

C．surfed

D．surfs

8 . Alice has a good temper. She always avoids ________ with other students.

A．to argue

B．argue

C．argues

D．arguing

9 . The money will be used for ________ the homeless animals.

A．helping

B．help

C．helps

D．helped

10 . Kitty has to ________ the piano every day.

A．practise to play	B．practising to play
C．practising playing	D．practise playing