Without facts , a person can’t form a correct opinion , for he needs to have actual knowledge his thinking .
| A．which to be based on | B．on which to base |
| C．which to be based | D．which to base |
When was it ______ you met Yao Ming in the street?
| A．as | B．if | C．while | D．that |
How happy we _______, if you had come with us to the party.
| A．could be | B．may have been |
| C．would have been | D．were |
It is required that no smoking ______ in the school.
| A．was allowed | B．be allowed |
| C．would be allowed | D．had been allowed |
The dress is not ______ for the formal party. You’d better find another one.
| A．appropriate | B．convenient | C．available | D．actual |
He was unable to make such progress, _______.
| A．as he tried hard |
| B．as hard he tried |
| C．so hard did he try |
| D．hard as he tried |