2020英语专四阅读练习100篇附答案:自然环境

　　2020英语专四阅读提高分数的方法肯定是平日大量的练习，华宇在线为大家整理了：2020英语专四阅读练习100篇附答案:自然环境 ，英语阅读是任何一个考试都有的题目，希望大家在平日不要松懈认真准备。

　　“The world's environment is surprisingly healthy. Discuss.”If that were an examination topic, moststudents would tear it apart. offering a long list ofcomplaints: from local smog (烟雾) to global climatechange, from the felling(砍伐) of forests to theextinction of species. The list would largely beaccurate,the concern legitimate. Yet the students who should be given the highest markswould actually be those who agreed with the statement. The surprise is how good things are, not how bad.

　　After all. the world's population has more than tripled during this century, and world outputhas risen hugely. so you would expect the earth itself to have been affected. Indeed, if peoplelived, consumed and produced things in the same way as they did in 1900 (or 1950. or indeed1980), the world by now would be a pretty disgusting place: smelly, dirty. toxic anddangerous.

　　But they don't. The reasons why they don't. and why the environment has not been ruined. have to do with prices. technological innovation, social change and government regulationin response to popular pressure. That is why today's environmental problems in the poorcountries ought. in principle, to be solvable.

　　Raw materials have not run out. and show no sign of doing so. Logically. one day they must: the planet is a finite place. Yet it is also very big. and man is very ingenious. What hashappened is chat every time a material seems to be running short, the price has risen and. inresponse. people have looked for new sources of supply, tried to find ways to use less of thematerial, or looked for a new substitute. For this reason prices for energy and for mineralshave fallen in real terms during the century. The same is true for food. Prices fluctuate, inresponse to harvests. natural disasters and political instability; and when they rise, it takessome time before new sources of supply become available. But they always do. assisted bynew farming and crop technology. The long-term trend has been downwards.

　　It is where prices and markets do not operate properly that this benign (良性的) trend beginsto scumble, and the genuine problems arise. Markets cannot always keep the environmenthealthy. If no one owns the resource concerned. no one has an interest in conserving it orfostering it: fish is the best example of this.