A:Hello,XXX What are you doing?

A:Hello,XXX What are you doing?
B:Hi,XXX.Look,I'm reading a book about Air pollution!
A:Air pollution ,That's very dangerous.
B:Right,Sandstorms(沙尘暴) and the dust and gases from volcanoes pollute the earth's atmosphere naturally.The sandsorms and volcanoes are dreariness.
A:But the most serious kind of air pollution comes from people.For example ,Factories,power stations,and rehicles exhausts pump harmful gases into the air.
B:And contributing to global warming,causing acid rain,and destroying the ozone layer.
A:What can we do something about Air pollution?
B:people can reduce air pollution by saving energy and reducing harmful emissions from vehicle exhausts and power stations.
A:Great,Air pollution is at its worst over big cities where millions of people live,work,and travel about in cars,buses,and trucks.
B:That's the answer why the cities have air pullution.
A:Factory chimmeys can be fitted with devices to cut down air pollution,but this is expensive.
B:Yes,If better pubic transport and cycle lanes were available in towns and cities,people would be less likely to use their cars,reducing the overall amount of pollution.
A:And we mustn't smoke,because Smoking cigarettes adds to the general levels of air pollution as well as damaging our health.
B:Good idea,Cigarette smoke contains chemicals that can cause cancer,a gas which stops oxygen being taken into the blood .
A:No-smoking areas can cut down on this pollution and save non-smokers breathing in other people's cigarette smoke.
B:We must protect our earth ourselves.

对啊