Ladies and gentlemen, please fasten your seat belts.The plane __________.
| A．takes off | B．has taken off | C．is taking off | D．took off |
—It can’t be too worse.
—Just _______. Things will turn out to be better so long as you don’t stop trying.
| A．be all right |
| B．take your time |
| C．ignore it |
| D．take it easy |
The villagers have already known _________ we’ll do is to rebuild the bridge.
| A．this |
| B．that |
| C．what |
| D．which |
The development of industry has been ________ gradual process throughout ________ human existence, from stone tools to modern technology.
| A．/; the |
| B．the; a |
| C．a; / |
| D．a; a |
—What shall we do tonight then?
—_______ -whatever you want.
| A．Help yourself |
| B．It’s a deal |
| C．No problem |
| D．It’s up to you |
It suddenly occurred to him ________ he had left his keys in the office.
| A．whether |
| B．where |
| C．which |
| D．that |