The earth is our home. We must take care of it. Life today is
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than it was hundreds of years ago, but it has brought some new problems. One of the biggest problems is pollution. We can see it,
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it, drink it and hear it.
Man has polluted the earth. The more people, the more pollution. Many years ago, the problem was not so
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., because there were not so many people. When the land was
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or the river was not clean in a place, man went to another place. Now man is slowly polluting the
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world.