Although the world is hungry, it is even thirstier.
虽然世界充满了饥饿，但是它更加缺水。
While nearly 3/4 of the earth is covered with water, we are still short of drinking water.
尽管地球的四分之三都覆盖着水，我们依然缺少饮用水。
This is because about 97% of the water on the earth is sea water.
因为地球上97%的水都是海水。
So we can't use it for watering plants or drinking directly.
所以我们不能用它来灌溉植物或直接饮用。
Humans can only drink and use fresh water from places including rivers, lakes and underground.
人类只能饮用来自河流、湖泊和地下的新鲜水。
How can we avoid a serious water shortage?
我们怎样能避免严重的水资源短缺呢？
First, we should save water and not waste it.
首先，我们应该储存水源，不再浪费。
Second, we should protect our water resources and not pollute them.
其次，我们应该保护水资源并且不再污染它们。
Third, we should discover ways to reuse water.
第三，我们应该寻找循环利用水源的方法。
Scientists have made some progress in this field.
科学在已经在这一方面取得了进步。
Today, some large cities are reusing their water.
现在，有些大城市的水源是重复利用的。
But people's need for water is increasing day by day.
但是人类对水资源的需求量与日俱增。
We still don't have enough water.
我们依然没有足够的水源。
What else can we do?
我们还能做什么呢？
The sea seems to have the best answer.
海洋似乎有最好的答案。
There is plenty of water in the sea.
大海有足够的水分。
But we need to take the salt away from the sea water.
但是我们需要把盐从海水中分离开来。
This is very expensive.
这花费很高。
If scientists can find cheaper ways to do it, we can solve the problem of the shortage of water.
如果科学家们能找到更便宜的方法，我们就能解决水资源短缺的问题。
