When we see well, we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.

　 People who are near-sighted can only see things that are very close to their eyes. Everything else seems blurry. Many people who do a lot of work, such as writing, reading and sewing become near-sighted. People who are far-sighted suffer from just the opposite problem. They can see things that are far away, but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading, they must get glasses, too.

　 Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism (散光). This, too, can be corrected by glasses. Some people’s eyes become cloudy because of cataracts (白内障). Long ago these people often became blind. Now, however, it is possible to operate on the cataracts and remove them.

　 Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself, look at an object out of one eye; then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distances as people with two eyes.

60. We should take good care of our eyes________.　　 .

A. only when we can see well　 B. only when we cannot see perfectly

C. even if we can see wel　　 D. only when we realize how important our eyes are

61.When things far away seem indistinct(模糊不清) , one is probably________.　　 .

A. near-sighted　 B. far-sighted 　　C. astigmatic　　 D. suffering from cataracts

62. The underlined word blurry in the second paragraph probably means_______.

A. obvious　　　 B. possible　　 C. clear　　 D. unclear

63. Having two eyes instead of one is particularly useful for_______　

A. seeing at night　 　　　　　 B. seeing objects far away

C. looking over a wide area　 　 D. judging distances

Using too much water or throwing rubbish into our rivers are clear ways that humans can put our water supply in danger, but we also affect our water supply in less obvious ways. You may wonder how paving(铺砌) a road can lead to less useable fresh water. A major part of the water we use every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave, the less water can flow into the ground to become groundwater.

  Human activity is not responsible for all water shortages. Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall, but in any case, good management can help to make sure there is enough water to meet our basic needs .

  Thinking about the way we use water every day can make a big difference, too. In the United States, a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live, but there’s a lot we can do to lower the number.

You can take steps to save water in your home. To start with, use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher only when it is full. Help your parents fix any leaks in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.

1.Which of the following is most likely to lead to less groundwater?

A. Using river water.                          B. Throwing batteries away.

C. Paving parking lots.                        D. Throwing rubbish into lakes.

2.What can be inferred from the text?

A. All water shortages are due to human behavior.

B. It takes a lot of effort to meet our water needs

C. There is much we can do to reduce family size.

D. The average family in America makes proper use of water.

3.The last paragraph is intended to     .

A. show us how to fix leaks at home

B. tell us how to run a dishwasher

C. prove what drinking glass is best for us

D. suggest what we do to save water at home

4.The text is mainly about      .

A. how human activity affects our water supply

B. how much we depend on water to live

C. why droughts occur more in dry climates

D. Why paving roads reduces our water

Using too much water or throwing rubbish into our rivers are clear ways that humans can put our water supply in danger, but we also affect our water supply in less obvious ways. You may wonder that paving(铺砌) a road can lead to less useable fresh water. A major part of the water we use every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave, the less water can flow into the ground to become groundwater. 

However, paving is not responsible for all water shortages. Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall, but in any case, good management can help to make sure there is enough water to meet out our basic need. 

Thinking about the way we use water every day can make a big difference, too. In the United States a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live, but there’s a list we can do to lower the number.

You can take steps to save water in your home. To start with, use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher(洗碗机) only when it is full. Help your parents fix any leaks (漏水) in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.

60. Which of the following is most likely to lead to less groundwater?

A. Using river water.                                

B. Throwing batteries away.

C. Paving parking lots.                             

D. Throwing rubbish into lakes. 
61. What can be inferred from the text? 

A. All water shortages are due to human behavior.

B. It takes a lot of effort to meet our water needs.

C. There is much we can do to reduce family size

D. The average family in America makes proper use of water. 
62. The last paragraph is intended to ________. 

A. show us how to fix leaks at home

B. tell us how to run a dishwasher

C. prove what drinking glass is best

D. suggest what we do to save water at home
63. The text is mainly about ________.

A. human activity affects our water supply

B. why paving roads reduces our water

C. how much we depend on water to live

D. why droughts occur more in dry climates

Using too much water or throwing rubbish into our rivers are clear ways that humans can put our water supply in danger , but we also affect our water supply in less obvious ways. You may wonder how paving(铺砌) a road can lead to less useable fresh water. A major part of the water we use every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave the less water can flow into the ground to become groundwater.
Human activity is not responsible for all water shortages(短缺). Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall, but in any case, good management can help to make sure there is enough water to meet our basic needs.
Thinking about the way we use water every day can make a big difference, too In the United States , a family of four can use 1. 5 tons of water a day! This shows how much we depend on water to live, but there’s a lot we can do to lower the number.
You can take steps to save water in your home. To start with use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher (洗碗机)only when it is full 。Help your parents fix any leaks in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.
【小题1】Which of the following is most likely to lead to less groundwater?