Pollution means any contamination of air, soil, water and environment. Even loud noise and sound are part of pollution. Pollution can be categorized into land, water and air pollution. Harmful gases and tiny particles (like carbon dioxide, nitrogen dioxide and sulphur dioxide) are polluting the air. The smoke released from burning fuel from factories and cars, are the major sources of air pollution. Air pollution is one of the major causes of that funny cough, asthma and burning eyes that you develop.
In addition to this, our water gets polluted because of the dirty water from our house, that drains through the pipes into the rivers and oceans dirtying the water. At last, plastic and dirt causes land pollution. We need to prevent all kinds of pollution to protect the environment. Besides ourselves, many animal species are the victims of pollutions.

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An Inconvenient Truth