人们总以为淡水是取之不尽的，实际上淡水资源是很有限的。请谈谈你的看法。
It is generally believed that there is a good supply of fresh water. But to our disappointment, the fact is just the opposite.
As we can see, the world population is growing rapidly day by day. So enough fresh water is needed to feed such a big population. What's more, with the development
