Mary is one of the brightest students who_________ from New York University.
| A．is graduated | B．have graduated |
| C．has graduated | D．are graduated |
– How soon could they cover the distance?
--- ____________.
| A．For two hours | B．During the two hours |
| C．After two hours | D．In two hours |
– Sir, we have failed to work out this problem. What is exactly the right way?
--- Look. Only in this way ________ , but you boys _____ a wrong way.
| A．you can work it out; take | B．you can work out it; take |
| C．can you work it out; take | D．can you work it out; took |
Not until he got to the factory _______that he had lost his papers.
| A．he found | B．did he find | C．had he found | D．has he found |
The animal is ______; we must do something to save it.
| A．dangerous | B．a danger | C．in danger | D．dangerous one |
.In that country about 80 percent of the population _____ farm.
| A．live on | B．lives on | C．live by | D．lives by |