What the doctors really doubt is _____my mother will recover from the serious disease soon.
| A．when | B．how | C．whether | D．why |
The young man insisted that he _____ nothing wrong and _____ free.
| A．did; set | B．had done; should be set |
| C．should do; be set | D．had done; must be set |
He is talking so much about America as if he _____ there.
| A．had been | B．has been | C．was | D．has gone |
________ is impossible for us to offer him any help.
| A．This | B．It | C．That | D．which |
So excited was the winner that he couldn’t say any word to his feelings.
| A．expose | B．convey | C．display | D．deliver |
How dirty the floor is! You should have someone _____ it at least twice a day.
| A．mop | B．to mop | C．mopping | D．mopped |