Environmental Pollution

Our environment is polluted by many pollutants. The gases emitted from factories and the exhaust pipes of automobiles pollute the air. Detergents and waste chemicals pollute rivers and other water supplies. Pesticides such as DDT leave poisonous residues in the tissues of organisms. Garbage cast out by people is left to accumulate in insanitary heaps which attract flies and give off bad smells.

These pollutants endanger public health. Once they have entered the environment, they are hard to get rid of. As people have to breathe, eat and drink them, they directly or indirectly affect bodily functions and cause many infections diseases.

Since we know where the pollutants come from and their harmfulness, we should take steps to clear away the sources of the pollution and establish a set of regulations to keep our environment free from pollution.

Notes:

这是一篇议论文。作者首先提出我们的环境被许多污染物污染，接着，作者论述了这些污染物对大家健康的危害。作者的结论是：清除污染源，制定法规，保护我们的环境不受污染。