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

If you travel in some areas of India, you’ll be lucky enough to be waited on by special guides（向导）― monkeys. These monkeys are always ready to serve you. Hungry, you just need to point to your own stomach and they’ll lead you to the nearest restaurant. Thirsty, the monkeys will lead you to a bar. Tired, you put both of your hands behind your head and the monkeys will take you to the nearest hotel. Don’t feel surprised when they put out their hairy hands to you after the service is done. They are just asking for a little money as a tip. After that, they will wave their hands as if they are saying goodbye to you.　

Believe it or not, these monkeys are from the school for monkeys in India, where they were trained for one year. They are not the only monkey students in the world. Some are being trained as nurses in an American medical college. These monkeys are about to look after patients and help them with their housework.　

A three-year-old monkey named Helen has learned to turn on TV, turn off lights, and open doors and windows when she is told to. Once the job is done, she will rush to her master, hoping to get some food as a reward.

50. When you’re thirsty, the monkey will lead you to ________.

　 A. a bar　　　　　　　　　 B. a hotel　　　　　　　 C. a restaurant　　　　　　 D. a shop

51. According to the passage, monkeys aren’t trained to ________.

　 A. open doors　　　　　　　　　　　 B. buy food

C. turn off lights D. look after patients

52. What is probably the best title for this passage?

　 A. Funny Monkeys　　　　　　　　 B. Lovely Guides　

C. Special Nurses D. Good Helpers