It was 1969 _____ the American astronauts succeeded in landing on the moon.
| A．that | B．when | C．on which | D．which |
Please call my secretary to arrange a meeting this afternoon，or __________ it is convenient to you.
| A．whenever |
| B．however |
| C．whichever |
| D．wherever |
At school, some students are active __________ some are shy, yet they can be good friends with one another.
| A．while |
| B．although |
| C．so |
| D．as |
—Derrick, don，t you think you should take a vacation? Even one or two days would be fine.
—There's __________. There's too much work.
| A．no problem |
| B．no way |
| C．no wonder |
| D．no need |
Cats and tigers are animals of the cat family (猫科动物), so cats __________ tigers in many ways.
| A．are similar to |
| B．are similar from |
| C．are different from |
| D．are different to |
The visitors you referred to __________ looking forward to __________ around our school.
| A．being ； be shown |
| B．being ； showing |
| C．are ； showing |
| D．are ；being shown |