He paid for a seat, when he________have entered free.
| A．could |
| B．would |
| C．must |
| D．need |
She thought I was praising her son, _____ as a matter of fact, I was scolding him for his bad behavior at school.
| A．while | B．therefore | C．which | D．so that |
The wreckage of something like a jet plain discovered in the heart of the desert is believed ______ a UFO and _______down for reasons still mysterious.
| A．to be; have fallen | B．to have been; to have fallen |
| C．to be; to fall | D．having been; having fallen |
The goods on this counter ____ at a discount of 25%, like the typewriters, television receivers, dustbins, etc.
| A．sell | B．sells | C．is sold | D．are sold |
It is every citizen’s duty to go out to ______ the snow on the street______ it stops falling so as to make it convenient for traffic to pass. .
| A．sweep up; the instant | B．clear up; the moment |
| C．clean up; immediately | D．whirled up; directly |
The most important _____ of the job as a typist is to be able to type fast and _______.
| A．aspect; accurate | B．way; exactly |
| C．aspect; accurately | D．part; precisely |