_____ human beings live in great numbers, the waters are very likely to become contaminated.
What __________the population of China? One-third of the population__________workers here.
The number of teachers in our college __________greatly increased last term.A number of teachers in this school __________from the countryside.
Onethird of the area__________covered with green trees.About seventy percent of the trees __________been planted.
More than one student in our class__________to the Great Wall.
Jane is getting on well with her classmates.Everyone in our class__________her.