No air means death. Although we can't see it, there is air round us.So air is everywhere and it gives life to every living thing. Without it we can't live. Bad air makes people ill.We must have fresh air to keep ushealthy.
In the city there are a great many people and there are too many cars running on the roads. The gas which the cars spread out is full of poison. Every day we breathe it in and out.
Besides so many cars, there are many factories too.From the chimneys of these factories, we get the smoke usually in a black or grey color. This kind of smoke, when it mixes with the air, is dangerous to our health. It is because smoke contains many small poisonous soils and gases. So in
order to keep healthy we have to go out to the countryside to breathe more fresh air. Or we can go up hills to get more fresh air.
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