．—Steve come back because the window is open．
—Yes．but he _______left it open last night．
| A．must have；might have | B．might have；can’t have |
| C．can have；should have | D．might；must have |
28. Be careful! The slightest spark（火花）could ______ the fireworks.
| A．set about | B．set off | C．set out | D．set up |
27. The police are offering a $ 60,000 _____ for information about the killer.
| A．price | B．prize | C．award | D．Reward |
26. People generally think that smoking is a bad ______ .
| A．custom | B．habit | C．behavior | D．Action |
25. We invited her to dinner but she didn’t even bother to _______ .
| A．turn in | B．turn up | C．turn on | D．turn down |
24. —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 |