IV
1, A- as
2, B – However
3, C – occurs
4, D – gaze
5, B – wasteful
6, B – lost
7, B – Too much
V
1, Air pollution can make people sick.
2, Smoke comes from factories.
3, Yes, it can.
4, The gases from the exhausts of cars have also caused air pollution in the cities.
5, Because the gases in the atmosphere continue to increase.
VI
1, Air pollution can directly contaminate the surface of bodies of water and soil.
2, We will save thousands of trees if we don’t waste so much paper.
3, What would you do if the air pollution got really bad?
4, Polluted water causes the death of aquatic animals such as fish and crabs.
5, If we recycled more, less rubbish went to landfill sites.