In order to have _____ better understanding of the accident, the three witnesses were called for _____ second meeting．
| A．a; a | B．the; a | C．a; 不填 | D．不填; the |
It was a time_______ the killer whales helped the whalers catch the baleen whales.
| A．when | B．that | C．then | D．which |
The most important thing about cotton in history is ______part that it played in _______Industrial Revolution.
| A．∕；∕ | B．the；∕ | C．the; the | D．a; the |
–Good morning． I’ve got an appointment with Miss Smith in the Personnel Department．
–Ah, good morning． You _____ be Mrs． Peters．
| A．might | B．must |
| C．would | D．can |
We _____ on this project for four hours． Let’s have a rest．
| A．are working | B．have been working |
| C．worked | D．had worked |
Would it be ______ for you to pick me up at four o’clock and take me to the airport?
| A．free | B．vacant |
| C．handy | D．convenient |