The world is not hungry ,but it is thirsty．It seems strange that nearly 3/4 of the Earth is covered with water while we say we are short of water．Why? Because about 97% of water on the earth is sea water which we can't drink or use for watering plants directly．Man can only drink and use the 3% of the water that comes from rivers and lakes．And we can't even 'use all of that, because some of it has been polluted．

Now more water is needed．The problem is: Can we avoid (避免) a serious water shortage later on? First, we should all learn how to save water．Second, we should find out the ways to reuse it．Scientists have always been making study in this field today, in most large cities water is used only once, then runs to the sea or rivers．

But it can be used again．Even if every large city reused its water, there still would not be enough．What could people turn to do next?

The sea seems to have the best answer．There is a lot of water in the sea．All that needs to be done is to get the salt out of the sea water．This is expensive, but it's already in use in many parts of the world．Scientist are trying to find a cheaper way of doing it．So you see, if we can find a way out, we'll be in no danger of drying up．

1．The world is thirsty because                     ．

A．3/4 of the earth is covered with water

B．we have enough sea water to use directly

C．we haven't used all the water in the rivers and lakes

D．about 97% of water on the earth can't be drunk or used for watering plants directly

2．Which of the following is true?

A．3% of water on the earth is in rivers and lakes．

B．75% of water on the earth is in the sea．

C．97% of the earth is covered with water．

D．3% of water on the earth is sea water．

3．From the passage we know                   ．

A．today in most large cities water is used only once

B．if every city reuses its water ,we'll be in no danger of drying up

C．man can only drink and use about 25% of water on the earth

D．water can be used only once

4．To avoid the serious water shortage (匮乏) , what should we do?

A．We should all learn how to save water．

B．We should find out the ways to reuse it．

C．Try to find a cheaper way to get the salt out of the sea water．

D．Do all the above things．

5．The title(题目) of the passage should be           ．

A．The Sea Water                                   B．How to save water

C．The Thirsty World                                D．The Polluted Water

The world is not hungry，but it’s thirsty.   1  while we say we are short of water.Why？Because about 97% of water on the earth is sea water which we can‘t drink or use for watering plants directly.Man can only drink and use the 3% of water that comes from rivers and lakes.   2  ，because some of it has been polluted.
　　Now more water is needed.The problem is how we can avoid a serious water shortage in the future.  3 Scientists are making study in this field.Today，In most large cities water is used only once and then runs to the sea or rivers.but it can be used again.Even if every large city reused its water，the water will still not be enough. 4 .
　　The sea seems to give us the best answer.There is a lot of water in the sea.All that needs to be get the salt out of the sea water.This will be expensive，but it has already been used in many parts of the world.   6 So you see，if we can find out a way，we’ll be in no danger of drying up.
从方框中所给的选项中选出能填入空白处的最佳选项，补全短文。其中有一项为多余选项。

The world is not hungry，but it’s thirsty.   1  while we say we are short of water.Why？Because about 97% of water on the earth is sea water which we can‘t drink or use for watering plants directly.Man can only drink and use the 3% of water that comes from rivers and lakes.   2  ，because some of it has been polluted.

　　Now more water is needed.The problem is how we can avoid a serious water shortage in the future.  3 Scientists are making study in this field.Today，In most large cities water is used only once and then runs to the sea or rivers.but it can be used again.Even if every large city reused its water，the water will still not be enough. 4 .

　　The sea seems to give us the best answer.There is a lot of water in the sea.All that needs to be get the salt out of the sea water.This will be expensive，but it has already been used in many parts of the world.   6 So you see，if we can find out a way，we’ll be in no danger of drying up.

从方框中所给的选项中选出能填入空白处的最佳选项，补全短文。其中有一项为多余选项。

E. First, we should find out ways to reuse it.

F. And we can’t even use all of that.