1 . The professor suggested that the students consider ________ more research on the topic.

A．do

B．doing

C．to do

D．done

2 . As we all know, it’s impolite to keep others ________ for a long time.

A．wait

B．to wait

C．waited

D．waiting

3 . Sara is used to ________ a glass of water when she gets up in the morning.

A．drink

B．drinks

C．drinking

D．drank

4 . When the police asked the doorkeeper about the theft, he denied ________ any stranger.

A．to see

B．seeing

C．see

D．saw

5 . Cindy, would you mind ________ me a lift to work tomorrow morning?

A．giving

B．to give

C．give

D．given

6 . Every time I pass by her office, she’s busy __________ something.

A．do

B．to do

C．done

D．doing

7 . Citizens in modern cities should consider ________ electric cars instead of fuel cars when going to work every day.

A．use

B．to use

C．using

D．used

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

A．eat

B．eating

C．ate

D．to eat

9 . As a lover of Chinese culture, Tina keeps         videos to learn about real life in China.

A．watch

B．watching

C．to watch

D．watched

10 . Look! Those little ants are busy _______ their food for the winter.

A．collect

B．collected

C．collecting

D．to collect