In your class, you should allow students to voice their opinions, they are different from your own.
| A．until | B．unless | C．even if | D．as though |
If Harry did not attend the conference last night, he________too much work to do.
| A．had to have had |
| B．had had |
| C．must have had |
| D．must have |
There was a lot of fun at yesterday's party. You________come, but why didn't you?
| A．might have |
| B．should |
| C．must have |
| D．ought to have |
—John, how did your maths exam go?
—I thought I________， but in fact I came in the top ten in the class.
| A．should have failed |
| B．couldn't have failed |
| C．might have failed |
| D．mustn't have failed |
As you worked late yesterday, you________have come this morning.
| A．mayn't |
| B．can't |
| C．mustn't |
| D．needn't |
The weather turned out to be fine yesterday. I________the trouble to carry my umbrella with me.
| A．should have taken |
| B．could have taken |
| C．needn't have taken |
| D．mustn't have taken |