Everyone knows ______ Olympic Games will be held in London in July, 2012.

Every year, _____people go to visit their factory

There are about _______ students in their school now..

Computers of today can work         than the ones in the 1970s.

_____of the warm water _____already been used up.

—Which is the biggest number of the four?
—           ．

--- Do you mind telling us something about this area?
--- Not at all. ________ of the land in this area _________ covered with trees and grass.

We know that 80          of the cases of blindness can          .

______ people were found ______ after that earthquake.

It is said that the gravity on Mars is only about          of the gravity on earth.