The park is far away from here indeed. It’s about _______ walk.
| A．a three hour | B．a three hour’s |
| C．a three-hours | D．a three- hour |
By the time I got to the airport, the plane ________.
A. took off B. has taken off C. had taken off
The boss in the factory made the workers_______nine hours a day in the past.
A. work B. to work C. working
I am a League Member. I volunteer my time _____ others.
A. help B. to help C. helping
---What did you do on April Fool’s Day?
---I played a trick ______ my brother.
A. on B. to C. with
Look at that girl ______ name is Lucy.
A. who B. whose C. which