The boys enjoy playing basketball __________ many of the girls relax by playing ping-pong.
| A．while | B．or | C．since | D．if |
With Shanghai World Expo drawing near, volunteers are making use of every minute to ________ their foreign language because language volunteers must pass a written test and an interview.
| A．polish up | B．take up | C．put up | D．make up |
The overseas Chinese scientist made another wonderful discovery, ___________ of great value to study AIDS.
| A．which I think it is | B．which I think is | C．I think it is | D．I think is |
The situation is _________ --- we have no food, very little water and no medical supplies.
| A．desperate | B．adventurous | C．deserted | D．optimistic |
The long-lasting meeting __________ in disorder, __________ no conclusion.
| A．was ended; reached | B．ended; reaching | C．was ended; reaching | D．ended; to reach |
He is only too ready to help others, seldom, _________, refusing them when they turn to him.
| A．if never | B．if ever | C．if not | D．if any |