Not until he left his home ______ to know how important the family was for him.
| A．did he begin | B．had he began |
| C．he began | D．he had begun |
-Would you mind if I take the seat?
- .
| A．Yes, sit down, please | B．Surely, never mind |
| C．No, not at all | D．No, you can’t take it |
The bell rang and came in Mr.Brown, a book in his hand. Then the class began.
| A．for | B．when | C．with | D．while |
In the past 5 years a great deal of money _____ improving the environment of the school.
| A．is spent | B．has been spent | C．was spent | D．had been spent |
China has been working very hard to stop the endangered animals ______ .
| A．dying out | B．dying away | C．dying down | D．dying hard |
I ______their method of making the machine .
| A．adopted | B． voted | C． elected | D． commanded |