He ___ without saying good-bye to them, for he always has good manners.
| A．mustn’t have left | B．may not have left | C．shouldn’t have left | D．can’t have left |
6．Be careful! The slightest spark（火花）could ______ the fireworks.
| A．set about | B．set off | C．set out | D．set up |
5．The police are offering a $ 60,000 _____ for information about the killer.
| A．price | B．prize | C．award | D．Reward |
4．—Where does your little daughter want to go during her holiday ?
—She is always looking forward to _____ to the Wu Yi Mountain.
| A．take | B．taking | C．being taken | D．b taken |
3．I’m preparing the report for tomorrow’s meeting. Would you please _____ the radio a little?
| A．turn on | B．turn off | C．turn up | D．turn down |
2．Great changes ______ in China in the past 20 years.
| A．took place | B．have taken place |
| C．were taken place | D．have been taken place |