【正确答案】自从地球上出现了人类，人类的生存很大程度上依靠自然。从我们吃的食物、喝的水到用来做家具的木头，几乎我们所有日常生活中要用的东西都来自大自然。
随着技术的发展和人口的增长，使用原材料的数量和范围以惊人的速度在增加。
然而，自然资源并不是取之不尽的。一些资源已濒临枯竭，没有再生的希望。普遍存在的水资源短缺就是一个相关的例子。
如果人类不为未来考虑，继续大肆浪费自然资源，就像卡通片里的例子那样，人类的后代结果只能以卖沙子为生，整个世界就会变得一团糟。

【答案解析】[听力原文]
Ever since man appeared on the earth, man's survival has heavily relied on nature. Almost everything we use in our everyday life comes from nature, ranging from the food we eat, the water we drink, to the wood which is turned into furniture.
With the development of technology and population growth, the amount and range of materials used has increased at an alarming rate.
However, natural resources are not inexhaustible. Some reserves are already on the brink of exhaustion and there is no hope of replacing them. The widespread water shortage is an example in point.
If man continued to squander natural resources with no thought for the future, the later generations would end up selling sand, as is the case in the cartoon, and the whole world would be in a mess.