I have a tight budget for the trip, so I'm not going to fly _ the airlines lower ticket prices.
| A．once | B．if | C．after | D．unless |
Hurry up! Flight 4406off at 18:40.
| A．takes | B．took | C．will be taken | D．has taken |
He liked to go to dances and parties, ______ he could have a good time just sitting and watching.
| A．where | B．when | C．which | D．why |
The Diaoyu islands have been part of China’s territory since ancient times, ______ as important fishing grounds of Taiwan.
| A．served | B．to serve | C．serving | D．having served |
—What’s that noise, John?
—Oh, don’t you know that the school library ?
| A．is rebuilt | B．is being rebuilt | C．was rebuilt | D．has been rebuilt |
On the way home, sky grew dark, andcold rain began to fall.
| A．the; 不填 | B．不填; the | C．the; a | D．不填; a |