You can never imagine _______difficulty we had _______the cupboard upstairs.
| A．what a; to carry | B．how; to carry |
| C．what; carrying | D．how; in carrying |
I _______ have been more than six years old when the accident happened.
| A．shouldn’t | B．couldn’t |
| C．mustn’t | D．needn’t |
—Why does Sara know so much about Angkor Wat?
—She _______ there,or she may have read about it.
| A．must have been |
| B．shouldn’t have been |
| C．may have been |
| D．can’t have been |
—Excuse me.Is this the right way to the Summer Palace?
—Sorry, I am not sure.But it _______ be.
| A．might | B．will |
| C．must | D．can |
You _______ be tired—you’ve only been working for an hour.
| A．must not | B．won’t |
| C．can’t | D．may not |
The engineers must have worked out the design by the end of last week，_______？
| A．mustn’t they | B．hadn’t they |
| C．haven’t they | D．didn’t they |