______ you understand it, it’s easy for you to obey it.
| A．As soon as | B．Once | C．Unless | D．The moment |
It was in the room _________ he was born _________ the meeting was held.
| A．that; that | B．where; that |
| C．which; where | D．where; which |
More than 10,000 competitors from the world came to Beijing to compete __________ each other __________medals in 2008
| A．with; for | B．for; against |
| C．against; with | D．for; with |
Some scientists believe that ________ is no doubt ________ a cure for AIDS will be found.
| A．it; that | B．it; whether |
| C．there; that | D．there; whether |
The teacher asked his students to leave a space in their exercise books ________.
| A．every a few lines | B．each a few lines |
| C．each few lines | D．every few lines |
The driver who died in the accident _________, but he didn’t wear the seat belt.
A. could survived B. could have survived
B. must survived D. must have survived