I like getting up very early in summer．The morning air is so good ______．
| A．to be breathed | B．to breathe |
| C．breathing | D．being breathed |
—Lucy doesn't mind lending you her dictionary.
—She________. I have borrowed one.
| A．can't |
| B．mustn't |
| C．needn't |
| D．shouldn't |
He________have completed his work; otherwise, he wouldn't be enjoying himself by the seaside.
| A．should |
| B．must |
| C．wouldn't |
| D．can't |
He paid for a seat, when he________have entered free.
| A．could |
| B．would |
| C．must |
| D．need |
________such heavy pollution already, it may now be too late to clean up the river.
| A．Having suffered |
| B．Suffering |
| C．To suffer |
| D．Suffered |
John, look at the time，________you play the piano at such a late hour?
| A．Must |
| B．Can |
| C．May |
| D．Need |