The girl has a great interest in sport and ____ badminton classes twice a week over the last three years.
| A．took | B．is taking |
| C．takes | D．has been taking |
21. He apologized ________ late.
| A．to his teacher to arrive | B．to his teacher for arriving |
| C．at his teacher to arrive | D．at his teacher for arriving |
20. I got up early this morning, but I ________ so because I was not on duty today.
| A．mustn’t have done | B．needn’t have done |
| C．didn’t need to do | D．can’t have done |
19. It’s dangerous to have the fire _______ at home all night long.
| A．to burn | B．burn | C．burned | D．Burning |
18. I decided to write about Chaplin, one of ______ films I had seen several years before.
| A．whose | B．whom | C．that | D．which |
17. Our attention was drawn to the eight-year-old girl who was _______ perfectly at the piano.
| A．acting | B．behaving | C．performing | D．doing |