29.Man-made satellites have been into space by many countries . A.set up B.sent off C.sent up D.sent for 查看更多

 

題目列表(包括答案和解析)



The rockets take astronauts and man-made satellites into space. The satellites are used for communication, weather monitoring and research. But how do satellites stay up without falling down?
There are two opposite forces (力量) acting on the satellite. One of them is the force of gravitation (地心引力), which tries to pull the satellite towards the earth. The other force is created by the rotation (旋轉(zhuǎn)) of the satellite around the earth. This force tries to take the satellite away from the earth. With these two forces, the satellite goes round and round. The gravitational pull of the earth (the force which pulls everything towards the ground) is like a rope which keeps the satellite from flying away.
Everything that goes up has to come down. It is only a matter of time before a satellite comes back to the earth. As time goes by, the satellite loses its speed, which makes the gravitational pull stronger than the force pulling it away. This makes the satellite crash (墜落) down to the earth.
【小題1】Which of the following uses of satellites is NOT mentioned?

A.communication
B.monitoring the weather condition
C.doing some research
D.taking pictures
【小題2】The force that pulls the satellite towards the earth is created by ________.
A.the earth
B.the satellite itself
C.the rotation of the satellite
D.the rope
【小題3】Why can’t the satellites fly away?
A.Because of the force from the earth.
B.Because the satellite is too big.
C.Because of the force created by the rotation of the satellite around the earth.
D.Because people on earth have made ropes to tie the satellites tightly.
【小題4】The satellite will finally crashes down to the earth ________.
A.when it flies faster
B.when its speed slows down
C.when people cut the rope
D.when there is no electricity in it
【小題5】Which of the following is TRUE according to the passage?
A.There are four forces acting on the satellite.
B.The force of gravitation makes the satellite go round and round.
C.As time goes by, the satellite will finally fall down.
D.The satellite will stay in space forever.

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根據(jù)漢語意思,完成下列句子。(每小題2分,共5小題,計(jì)10分)
【小題1】你給我這么多幫助,你真好。
               to give me so much help.
【小題2】大部分時(shí)間我們都在一起;因此我們從不覺得寂寞。
We are together most of the time, so we              
【小題3】珍愛自己,遠(yuǎn)離不健康的書。
Take good care of yourself and              bad books.
【小題4】近五年來在西昌已發(fā)射了幾顆人造衛(wèi)星。
Several man-made satellites             in Xichang in the past five years.
【小題5】我認(rèn)為自己想辦法要比仿照別人的樣子要好。
I think it's better to find our own way than             .  

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根據(jù)漢語意思,完成下列句子。(每小題2分,共5小題,計(jì)10分)
【小題1】你給我這么多幫助,你真好。
               to give me so much help.
【小題2】大部分時(shí)間我們都在一起;因此我們從不覺得寂寞。
We are together most of the time, so we              
【小題3】珍愛自己,遠(yuǎn)離不健康的書。
Take good care of yourself and              bad books.
【小題4】近五年來在西昌已發(fā)射了幾顆人造衛(wèi)星。
Several man-made satellites             in Xichang in the past five years.
【小題5】我認(rèn)為自己想辦法要比仿照別人的樣子要好。
I think it’s better to find our own way than             .  

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       Man-made satellites have been sent up into space by many countries. These satellites go round the earth and help us to learn more about the earth, the weather and other things. Most countries use these satellites to sent and receive messages. For example, with their help China can send their programs to America, too. We can also use satellites to help us to make telephone calls to foreign countries.
【小題1】These satellites go round ____.
A.the earthB.the moonC.the sunD.the stars
【小題2】 Man-made satellites are ____ to people.
A.terribleB.usefulC.unknownD.not necessary
【小題3】 Without the help of man-made satellites, we couldn’t see ____ on TV.
A.a(chǎn)nything interestingB.what other people are doing
C.foreign programsD.colour films
【小題4】Man-made satellites can also help us ____ to our friends on the other side of the world.
A.write downB.send birthday presents
C.pay visitD.make telephone calls

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_________ the help of man-made satellites, we can know what the weather will be like

in the next few days.

A.Under

B.With

C.Using

D.By

 

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