The environment is usually changed to benefit human life.

环境通常是改变人类生活的利益。

Cars and roads make transportation fast and easy, factories make products that make our lives more comfortable, public services in cities like water treatment, electricity, and waste disposal make our lives more convenient.

汽车和道路使交通运输快捷方便，工厂生产的产品使我们的生活更舒适，在城市的公共服务，如水处理，电力，和废物处理，使我们的生活更方便。

All of these advances, however, come with a significant environmental cost.

所有这些进展，但是，有一个显着的环境成本。

Human activity does significant damage to the Earth.

人类活动对地球造成重大损害。

One of the main effects of human activity on an area is water pollution.

人类活动对一个地区的主要影响之一是水污染。

Dumping waste materials from human activity into rivers and streams is popular because the waste seems to disappear downstream.

从人类活动到河流和小溪的倾倒废物的材料是流行的，因为废物似乎消失了下游。

The main sources of water pollution are factory waste, oil and gas runoff from highways, and untreated human waste.

水污染的主要来源是工厂的废水、公路的石油和天然气，以及未经处理的人类废物。

When this waste dumped into rivers, the water downstream becomes undrinkable and unusable for agriculture, and also kills plant and animal life in the rivers.

当这些废物排入河流，下游的水就不能喝，不能用于农业，并杀死植物和动物生命的河流。

Clean air and water is a prerequisite not only for human life, but also for all life on the planet.

清洁空气和水是人类生活的前提，也是地球上所有生命的先决条件。

But air is now being polluted by modern transportation, notably gas-powered automobiles, as well as electrical generators that burn fossil fuels and pour polluting chemical waste into the air.

但是，现在的空气污染正受到现代交通运输业的污染，尤其是天然气汽车，以及燃烧矿物燃料的发电机，把污染的化学废物倾倒在空气中。

This makes the air much less healthy to breathe.

这使得空气更不健康的呼吸。

The air-borne pollution also falls back to the earth in the form of acid rain, which destroys plant life and human buildings.

空气污染的污染也以酸雨的形式返回到地球，这破坏了植物的生命和人类的建筑。

Another serious long-term effect of air pollution is global warming.

空气污染的另一个严重的长期影响是全球变暖。

For the past several decades scientists have noted a disturbing rise in the average temperature of the earth that caused by the rise of greenhouse gases, air pollutants created by burning fossil fuels, in the atmosphere.

在过去的几十年里，科学家们已经注意到地球的平均温度上升了一个令人不安的上升，温室气体的增加，燃烧矿物燃料产生的空气污染物，在大气中。

Scientists believe that if humans continue to increase the amount of greenhouse gases in the atmosphere, the temperature of the earth will continue to rise.

科学家认为，如果人类继续增加大气中温室气体的量，地球的温度将继续上升。

Eventually, this could melt the polar ice caps and cause devastating costal flooding all over the world.

最终，这会融化极地冰盖和世界各地的沿海洪灾造成毁灭性的。

Major cities like Hong Kong, Shanghai, and Dalian might be totally destroyed.

像港、上海、大连这样的大城市，可能会被彻底摧毁。

Therefore, I believe human activity has caused serious problems while it has improved the world in which we live.

因此，我相信人类活动在改善我们生活的世界的同时，也带来了严重的问题。

It is time to realize this hazard and take action to prevent further disaster while making progress.

是时候认识到这一危险，并采取行动，以防止进一步的灾难，同时取得进展。

编辑:Liuxuepaper.Com