By the time he realizes he ______ into a trap, it’ll be too late for him to do anything about it.
| A．walks | B．walked | C．has walked | D．had walked |
The computer system ____ suddenly while he was searching for information on the Internet.
| A．broke out | B．broke down | C．broke up | D．broke in |
Many students joined in the ____ race in the sports meeting to be held next week.
| A．800-meter-long | B．800-meters-long | C．800 meter long | D．800 meters length |
___ and out of breath, we reached the top of the mountain and stopped ____ the beautiful scenery.
| A．Tiring, to admire | B．Being tired, admiring | C．Tired, to admire | D．Tired, admiring |
I think you need some outdoor exercise. Plenty of fresh air will ___ good health.
| A．devote to | B．contribute to | C．apply to | D．adjust to |
I have read the material several times but it doesn’t make any ____ to me.
| A．meaning | B．importance | C．sense | D．sign |