Sending man into ______ space is not _____dream for human beings any longer.
| A．/; a | B．the; a | C．the; the | D．/; the |
(2012·安徽) The limits of a person's intelligence, generally speaking, are fixed at birth, but __________ he reaches these limits will depend on his environment.
| A．where |
| B．whether |
| C．that |
| D．why |
It suddenly occurred to him __________ he had left his keys in the office.
| A．whether |
| B．where |
| C．which |
| D．that |
—Do you think their table tennis team will win the first place at the coming Asian Games?
—__________. Ours is much stronger than theirs.
| A．Of course |
| B．It depends |
| C．Don't mention it |
| D．By no means |
The death rate is __________ pigs and recovery usually __________ within 7—10 days.
| A．low in; occurs |
| B．rich in; happens |
| C．high in; came about |
| D．poor in; took place |
__________ is certain is __________ prevention is more important than treatment.
| A．It; that |
| B．What; that |
| C．As; what |
| D．What; what |