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Air is very important to everything that lives. But the air we breathe is g 1 dirty. People all over the world
are looking for w 2 to make it clean again.
Have you e 3 watched the smoke from chimneys rising high in the air? Have you s 4 the smoke from
cars and trucks on roads or the smoke from planes? The smoke is not g 5 to breathe. If we want to keep
well and strong, we need to breathe c 6 air.
W 7 more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p 8 .
Scientists have a 9 found ways to stop or slow down some of the things that make the air dirty. They
will not stop working u 10 we have clean air again. We hope our environment will be better and better.
