_______ human beings use it in a wrong way, like we did with nuclear technology, the advancement of science and technology has never led to decline of human development.
| A．While | B．Unless |
| C．As long as | D．Before |
— I phoned you yesterday morning. A girl answered, but I didn’t recognize the voice.
— Oh, it __________ my younger sister. She was in my room at that moment.
| A．must have been | B．should have been |
| C．could have been | D．may have been |
He _______ Alice for ten years.
| A．married to | B．has married to |
| C．has married | D．has been married to |
He hesitated for a moment before kicking the ball, otherwise he ______ a goal.
| A．had scored | B．scored |
| C．would score | D．would have scored |
The river ____are covered with trees is very long
| A．which banks | B．of which banks |
| C．whose the banks | D．the banks of which |
----I missed the first part of the film. It was really a pity．
----You _____home half an hour earlier.
| A．should have left | B．must have left |
| C．should leave | D．must leave |