—Why can't I smoke here?
—At no time__________ in the meeting-room
| A．is smoking permitted | B．smoking is permitted |
| C．smoking is it permitted | D．does smoking permit |
20. "What can I do for you?" or "May I help you?" is a pet phrase used by _____ .
| A．an assistant engineer | B．an assistant manager |
| C．a helper | D．a shop assistant |
21. Move a few steps, and the oil-paintings look better ______.
| A．in the distance | B．at once | C．in the open air | D．at a distance |
22. In fact, the untruthful words made ____ on me. You must answer for that.
| A．a surprise attack | B．much damage | C．a personal attack | D．a great harm |
23. Every Monday morning, all the teachers and students in our school stand at ____ as our national flag is raised.
| A．attention | B．attentions | C．at ease | D．Attentively |
24. --- What are the greatest ____ ?
--- A giant panda.
attraction B. attractions C. attractive D. Attract