I________have gone the concert because I know nothing about that kind of music.
| A．couldn’t | B．mustn’t | C．shouldn’t | D．oughtn’t |
At the school gate, you should _____ the safeguard with your student card.
| A．present | B．give |
| C．show | D．provide |
Father insisted Tom _____ all his homework before he went to bed.
| A．finishing | B．to finish |
| C．finish | D．finished |
I met this guy _____ some other occasions but he did not seem to recognize me.
| A．for | B．on |
| C．at | D．in |
I don’t like the lecture yesterday. Most of what the speaker said was _____ the subject.
| A．on | B．off |
| C．of | D．around |
The demand for _____ skilled workers is still increasing.
| A．high | B．higher |
| C．highly | D．more highly |