Solids can be turned into liquids if we raise their temperature high enough.That is called a . A. chemical change B. physical change C. chemical state D. physical state 查看更多

 

题目列表(包括答案和解析)

从括号中选出适当的词填空。

If we ______ (raise, rise) their temperatures high enough, 

solids can be turned into liquids.

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Solids can usually be turned into liquids and liquids into gases if their temperatures ______ high enough.

[    ]

  A. raise   B. rise   C. are risen   D. is raised

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根据短文内容,完成下列句子。
     No air means death. Although we can't see it, there is air around us. So air is everything and it gives life to
every living thing. Bad air makes people ill. We must have fresh air to keep us in good health.
     In the city, there are a great many people and there are too many cars running on the roads. The gas which
the cars give out is full of poison (有毒物). Every day we breathe it in again and again. This makes us feel sick.?  Besides cars, there are many factories, too. From chimneys (烟囱) of these factories, the smoke is usually
black or grey. This kind of smoke, when mixed with the air, is dangerous to our health. It is because the smoke
contains many poisonous solids and gases. In order to keep us healthy, we have to go out to the countryside to
breathe more fresh air. We can also climb up hills to get the fresh air.?
1. We can't              if there is no air.?
2. People will have good health only when they breathe             .?
3. The poisonous gas can make people             .?
4. The              from the chimneys of the factories is usually black or grey.
5. We should often go to the               to breathe more fresh air.

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阅读理解。
     No air means death. Although we can not see it, there is air round us. So air is everywhere and it gives
life to every living thing. Without it we can not live. Bad air makes people ill. We must have fresh air to
keep us in good health.
     In the city there are a great many people and there are too many cars running on the roads. The gas
which the cars spread out is full of poison. Everyday we breathe it in again and again. This makes us feel
sick. Therefore people should go out of door as much as they can.
     Besides so many cars, there are many factories too. From the chimneys of these factories, we get the
smoke usually in black or grey colour. This kind of smoke, when it mixes the air, is dangerous to our health.
It is because smoke contains many small poisonous solids and gases. So in order to keep us healthy we have
to go out to the countryside to breathe more fresh air. Or we can go up hills to get more fresh air.
1. which of the following titles is the best for this passage?
[     ]
A: Air
B: Fresh Air
C: Breathing Air
D: The Use of Air
2. ____ could live without air.
[     ]
A: Fish
B: Anything
C: Fruit
D: Nothing
3. Although we can not see it there is _____ all around us.
[     ]
A: gas
B: poison
C: water
D: smoke
4. Air gives ____to all living things.
[     ]
A: life
B: live
C: death
D: health
5. We must have fresh air to keep our ____.
[     ]
A: breath
B: health
C: wealth
D: death

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(阅读理解)

No air means death. Though we cannot see it, there is air round us. So air is everywhere and it gives life to every living thing. Without it we cannot live. Bad air makes people ill. We must have fresh air to keep us in good health.

In the city there are a great many people and there are too many cars running on the roads. The gas, which the cars spread out, is full of poison. Everyday we breathe it in again and again. This makes us feel sick. Therefore people should go out of door as much as they can. Besides so many cars, there are many factories, too. For the chimneys of these factories, we get the smoke usually in black or gray color. This kind of smoke, when it mixes the air, is dangerous to our health. It is because smoke contains many small poisonous solids to gases. So in order to keep us healthy we have to go out to the countryside to breathe more fresh air. Or we can go up hills to get more fresh air.

(1)

What’s the main idea of the story?

A. Air.  

B. Fresh air.

C. Breathing air.

D. The use of air.

[  ]

(2)

_______ could live without air.

A. Fish  

B. Nothing  

C. Fruit  

D. Anything

[  ]

(3)

Though we can’t see it there is _______ all around us.

A. gas  

B. poison  

C. water    

D. air

[  ]

(4)

Air gives _______ to all living things.

A. live  

B. life  

C. death  

D. health

[  ]

(5)

We must have fresh air to keep our _______ .

A. breath  

B. health

C. wealth  

D. death

[  ]

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