________is well known that great changes have taken place in China recently.
| A．That | B．As | C．Which | D．It |
The dooropen , no matter how hard she pushed.
| A．shouldn’t |
| B．couldn't |
| C．wouldn't |
| D．mightn't |
Since nobody gave him any help, he have done the research on his own.
| A．can |
| B．must |
| C．would |
| D．need |
No onebe more generous; he has a heart of gold.
| A．could |
| B．must |
| C．dare |
| D．need |
—Why are your eyes so red? You _______ have slept well last night.
—Yeah, I stayed up late writing a report.
| A．can’t |
| B．mustn’t |
| C．needn’t |
| D．won’t |
21. The children lost in the woods; otherwise, they would have been at the lakeside camp as scheduled.
| A．must have got |
| B．must get |
| C．should have got |
| D．should get |