We have just heard a warning on the radio _____________ a typhoon may be on its way．
| A．what | B．when | C．which | D．that |
Have you ever wondered why some of the smartest students in your class sometimes ________ failing exams?
| A．take up | B．pick up | C．come up | D．end up |
In 1986, the Chinese government ________ a law stating that by the year 2000 every Chinese child would have nine years of compulsory education.
| A．impressed | B．introduced | C．interrupted | D．instructed |
Their products enjoy 30 percent ________ of the market in this country because both the quality and their service are fine.
| A．features | B．shares | C．interests | D．sales |
With temperature ________ so rapidly, we could not go with the experiment.
| A．fall | B．falling | C．fallen | D．to fall |
How did it ________ that the ancient building was burnt down in an hour?
| A．happen | B．occur | C．take place | D．come about |