Section CAbout 70% of the earth's surface is covered with water, but only a little percent

Section C

About 70% of the earth's surface is covered with water, but only a little percentage of water is 【11】______. Life on the earth entirely depends on water. It is a fact that man can live without food for days, but without water he will【12】______die soon.

Water serves us in so many useful ways. The rivers, lakes and seas provide much of our food such as fish and prawns. Men have built boats and ships to enable them to travel on water. Today cargo and 【13】______ships can travel around the world.

In【14】______parts of the world where there is not much rain. Water is led from rivers and lakes to water crops. In many parts of these dry regions,【15】______is difficult unless there is enough water.

But too much water in the form. of floods can bring disaster to man. Floods, which result from heavy rains, are very common in many parts of the world. Each year thousands of people die and huge damage is done by floodwaters.

【11】

A．drinking

B．drinkable

C．drinker

D．drunk