Either you or one of your students___to attend the meeting__ tomorrow.
| A．are; to be held | B．is；being held | C．is; to be held | D．are；having held |
The most impressive sight in China，one of the wonders of the world，_____ the Great Wall.
| A．is | B．are | C．was | D．were |
The factory used 65 percent of the raw materials,the rest of whichsaved for other purposes.
| A．is | B．are | C．was | D．were |
—Why does the lake smell terrible?
—Because large quantities of water_______________.
| A．have polluted | B．is being polluted |
| C．has been polluted | D．have been polluted |
One-third of the country____covered with trees and the majority of the citizens_______black people.
A is；are B is；is C.are；are D.are；is