The number of foreign students attending Chinese universities ________ rising steadily since1990. 
| A．is | B．are | C．has been | D．have been |
Yang Liwei showed the flags of China and the United Nations, ________ the wishes of Chinese people to use space peacefully.
| A．expressing | B．expressed |
| C．to express | D．express |
-- The last one ________ pays the meal. --- Agreed.
| A．arrived | B．to arrive |
| C．arrives | D．arriving |
She had to leave school_______ her family couldn’t afford her education.
| A．although | B．unless |
| C．because | D．so |
The old man has retired from the factory. He _____ there for 30 years.
| A．works | B．worked |
| C．has worked | D．was working |
— I don’t mind telling you what I know.
— You _______. I can manage it myself.
| A．mustn’t | B．ought not to |
| C．can’t | D．don’t have to |