—This wall of air is an effective answer to the problem and it ______ work.
—But it is a question to put such a wall of air around the statue.
| A．may | B．must | C．should | D．could |
She paused________over the unfamiliar word but soon continued.
| A．frequently | B．briefly |
| C．anxiously | D．casually |
It is reported that a similar technique can be________to the treatment of cancer.
| A．applied | B．attached |
| C．added | D．compared |
—Tom often plays the record very loud at midnight in his apartment.
—________！
| A．Just your luck | B．Better not |
| C．It can’t be helped | D．That’s too much |
The children________very well last night and the audience were attracted by their play.
| A．permitted | B．performed |
| C．pretended | D．presented |
It is________tradition for people in this country to pay in________cash when buying things.
| A．the；/ | B．a；/ |
| C．；/the | D．a；the |