We _______ on this project for four hours. Let’s 
have a rest.
| A．are working | B．have been working | C．worked | D．had worked |
Dickson left his father’s firm and ____business on his own.
| A．started out | B．launched into | C．began on | D．worked at |
There is no doubt _______international cooperation is the key to dealing with cyber crime.
| A．then | B．that | C． wheather | D．this |
Considering your salary, you should ________ at least 100 dollars a week.
| A．put up | B．put forward | C．put aside | D．put out |
The sunlight is white and blinding _______ hard-edged shadows on the ground.
| A．throwing | B．being thrown | C．to throw | D．to be thrown |
Some green beans, ______ long enough, can be poisonous (有毒的).
| A．if not be cooked | B．if not cooked | C．if not cooking | D．if not being cooked |