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阅读理解。

　　Rockets(火箭)can fly far out into space．Rockets with men inside them have already reached the moon in the USA and Russia．Several rockets without men inside them have been sent to other worlds much farther away．On Nov．7, 2007, China’s first lunar probe, Chang’e I, successfully has completed its 1,580,000 km flying journey to the moon．

　　I am sure that you are asking ‘How does a rocket fly?’ If you want to know, get a balloon and then blow it up, until it is quite big．Do not tie up the neck of the balloon, let it go．The balloon will fly off through the air very quickly．The air inside the balloon tries to get out．It rushes out through the neck of the balloon and this pushes the balloon through the air．

　　This is how a rocket works．Of course, the rocket is made of metal．The metal must not be heavy but it must be very strong．There is gas inside the rocket, which is made very hot．When it rushes out of the end of the rocket, the rocket is pushed up into the air．The jet velocity(喷射速度)is always faster than the flying speed．

　　We’re sure that one day rockets with man may be able to go anywhere in space．

(1)

Look at the following pictures, if ‘U’ means ‘jet velocity’, ‘V’ means ‘flying speed’, which picture is RIGHT?
[　　]
A．
B．
C．
D．

(2)

The underlined word ‘it’ here refers to ________．
[　　]
A．	the rocket
B．	the metal
C．	the air
D．	the hot gas

(3)

Which of the following is NOT right?
[　　]
A．	Men have been to the moon by rocket．
B．	It’s about 1,580,000 km from the moon to the earth．
C．	A balloon can fly if the air in it goes out completely．
D．	The hot gas inside the rocket can make it fly．

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阅读理解

　　Rockets(火箭)can fly far out into space．Rockets with men inside them have already reached the moon in the USA and Russia．Several rockets without men inside them have been sent to other worlds much farther away．On Nov．7, 2007, China’s first lunar probe, Chang’e I, successfully has completed its 1,580,000 km flying journey to the moon．

　　I am sure that you are asking ‘How does a rocket fly?’ If you want to know, get a balloon and then blow it up, until it is quite big．Do not tie up the neck of the balloon, let it go．The balloon will fly off through the air very quickly．The air inside the balloon tries to get out．It rushes out through the neck of the balloon and this pushes the balloon through the air．

　　This is how a rocket works．Of course, the rocket is made of metal．The metal must not be heavy but it must be very strong．There is gas inside the rocket, which is made very hot．When it rushes out of the end of the rocket, the rocket is pushed up into the air．The jet velocity(喷射速度)is always faster than the flying speed．

　　We’re sure that one day rockets with man may be able to go anywhere in space．

(1)

The underlined word ‘gas’ in the passage means _________．
[　　]
A．	气体
B．	液体
C．	汽油
D．	气球

(2)

Look at the following pictures, if ‘U’ means ‘jet velocity’, ‘V’ means ‘flying speed’, which picture is RIGHT?
[　　]
A．
B．
C．
D．

(3)

The rocket is made of _________．
[　　]
A．	light and strong metal
B．	heavy and strong metal
C．	light and strong gas
D．	heavy and strong gas

(4)

The underlined word ‘it’ here refers to _________．
[　　]
A．	the rocket
B．	the metal
C．	the air
D．	the hot gas

(5)

Which of the following is NOT right?
[　　]
A．	Men have been to the moon by rocket．
B．	A balloon can fly if the air in it goes out completely．
C．	It’s about 1,580,000 km from the moon to the earth．
D．	The hot gas inside the rocket can make it fly．

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阅读理解

“Life is speeding up(加快速度). Everyone is getting unwell.” This may sound like something someone would say today. But in fact, an unknown person wrote it.

Inventions can change our lives. But have all these things really improved our lives? Imagine this. You’re doing your homework on the computer. Your mobile phone rings and the noise from the television is getting louder and louder. Suddenly the computer is turned off and you lose all your work. How do you feel? Inventions have speeded up our lives, but they often leave us feeling tired.

One family in England went “back in time” to see what life was like without these inventions. The grandparents, with their daughter and grandsons Ben 10 and Tom 7, spent nine weeks in an old house. They had no computers or mobile phones. The grandmother, Linda, said, “The more things you have, the harder life becomes.” And Ben also noticed that his grandmother had changed. She cooked delicious food for them!

根据短文内容，选择正确答案。

1.The writer uses the quotation(引语) at the beginning to _____.

A．tell us a truth about our lives	B．tell us what life was like before
C．show why such a thing happened	D．show that we face big problems

2.In the passage the writer describes a picture to show that new inventions _____.

A．have speeded up our lives	B．have improved our lives
C．may make people feel happy	D．may bring people some trouble

3.The family chose to spend some time in an old house because _____.

A．they loved to live simple lives

B．they wanted to know how people lived without modern inventions

C．they were troubled by modern inventions

D．living in a different way would be fun for them

4. According to the passage, which of the following is NOT true?

A．With the improvement of our lives, we often feel tired.

B．An unknown man was sure that life would get better.

C．The family had some changes when they lived in an old house.

D．The grandson Ben was ten when the family went “back in time”.

5.The passage is mainly about _____.

A．problems with technology	B．improvements of our lives with technology
C．changes happening to technology	D．the importance of technology

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　　Strong winds, sand in the air, poor visibility(能见度), we all know the characteristics(特点)of a sandstorm．But what else do you know about them?

　　Do you know for example, that the first sandstorm of 2009 hit north China's Inn Mongolia late February?

　　Sandstorms are today a special treat of life in northern China because of desertification(沙漠化)and the retreat(退化)of northern grasslands．They usually occur(出现在)between February and May．

　　Fortunately, sandstorms this year should be fewer than in past years in north China, according to the National Meteorological Center(中央气象台)．

　　And the chances of sandstorms hitting Beijing are small, because recent rain has stopped drought(旱灾)．Tree planting, and other measures taken by the government, has also helped decrease the chance of sandstorm in the city．

　　Sandstorms can be dangerous．However, there are measures you can take to protect yourself from harm．

　　◆Wear a mask．Cover your nose and mouth with a mask that can keep out sand, or use a wet handkerchief．

　　◆If you are driving and the storm is far away from you, it may be possible to outrun it．If it looks like you will be caught in the storm, stop and wait it out．

　　◆Take cover．If there is no shelter, then lie down．Keep eyes, nose and mouth covered．Cover your head with your arms or a backpack to protect yourself against flying objects．

　　If you are caught in a desert sandstorm, take the following action．

　　◆Mark your direction before lying down．It is easy to get lost in a desert．

　　◆Keep plenty of water at hand．If you get lost, you need water to keep your life until you find your way or help arrives．

　　◆Stay together if traveling in a group．Lock arms if caught in a sandstorm．

　　The most useful measure would actually be to make sandstorms disappear forever．To make this goal come true, people should plant trees, and stop desertification．

　　Today, the straight-line distance between Tian'anmen Square and a desert called Tianmo in Hebei province is only about 80km．If desertification is not stopped, environmental protection experts say, it will probably not be long until Beijingers can catch a camel to work．

(1)

Which of the following is NOT the characteristic of a sandstorm?
[　　]
A．	Strong winds．
B．	Sand in the air．
C．	Poor visibility．
D．	Heavy snow．

(2)

According to the passage, which of the following statements is true?
[　　]
A．	So far in 2009 no sandstorm has happened．
B．	Sandstorms usually happen in spring．
C．	Sandstorms are a part of life in China．
D．	In sandstorms, what you need to do is just to lie down．

(3)

In order to protect you from harm in a sandstorm, which may NOT be the right action to take?
[　　]
A．	Finding a shelter．
B．	Covering your head with a bag．
C．	Lying down to wait．
D．	Speed up and rush through the sandstorm．

(4)

What can we infer from the passage?
[　　]
A．	North China has been hitting by sandstorms for several years．
B．	80 km has made the chances of sandstorms hitting Beijing small this year．
C．	Planting trees can help make sandstorms disappear．
D．	It is more dangerous in cities because there are more flying objects．

(5)

What's the best title of this passage?
[　　]
A．	Protecting Environment
B．	Flying Objects
C．	Sandstorm Realities
D．	Strong Winds

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The Slowest and the Fastest

　　The state of Florida was once almost gobbled (大吃) up by snails(蜗牛). They were giant(巨大的) snails from Africa. A visitor took some to Florida, where they spread quickly. Some of the snails were as big as a person's hand. They ate the leaves on trees and other plants. They had to be stopped, and they were. Poison killed thousands of the snails, and Florida was saved.

　　Catching a snail should be easier than catching any other animal. The snail is the slowest of all land animals. Its top speed is 55 yards per hour. At this speed it would take the snail about 32 hours to travel one mile. A snail only goes that fast when it's very hungry.

　　The bar graph below shows some other top speeds.

　　A bar graph has bars of different lengths, instead of pictures. This kind of graph makes it easy to compare several things quickly. To read the graph, notice where each bar ends. Then find the closest number at the bottom of the graph.

　　Use the bar graph about running speeds to answer the questions.

1．What is the top speed of a rabbit?

[　　]

A．30 miles per hour

B．35 miles per hour

C．40 miles per hour

D．50 miles per hour

2．Fifty miles per hour is the top speed for ________ .

[　　]

A．a rabbit

B．a human

C．a greyhound

D．a gazelle

3．What is the difference in running speed between a greyhound and a gazelle?

[　　]

A．5 miles per hour

B．10 miles per hour

C．15 miles per hour

D．20 miles per hour

4．The closest to an elephant in running speed is ________ .

[　　]

A．a human

B．a greyhound

C．a chicken

D．a rabbit

5．A rabbit and greyhound can both run faster than ________ .

[　　]

A．50 miles per hour

B．45 miles per hour

C．40 miles per hour

D．30 miles per hour

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