5．Why can’t the kid go to the party on Wednesday? 【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.

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

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 

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.

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

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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請根據(jù)句意從方框中選擇合適的動詞，并用其適當(dāng)時態(tài)填空，使句子通順。

destroy       control      help        steal      drop      
 
【小題1】Don’t worry about the girl too much. Her temperature __________back to normal if she takes this medicine.  
【小題2】Who __________ my new bike? I can’t find it anywhere. I put it here last night.
【小題3】People often __________ forests to build roads in the past. Now they have stopped doing so.
【小題4】When I passed him just now, he ___________ the icon on the computer with the mouse.
【小題5】— Why can’t she go to play basketball with us at present?
— She __________ her mother with the housework.

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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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閱讀下面的短文，完成文后的任務(wù)。
     An elephant and a monkey are good friends. They are both (都) proud (驕傲). The elephant says
 "Look, how big and strong (強(qiáng)壯) I am!" The monkey is proud because he is smart. He says "Can you
 climb a tree?"
    There is a tall banana tree on the island (島). (4) They want to cross the river (河) to the island and get
 some bananas. The elephant can cross the river, but he can not reach the bananas because the tree is too
 tall. The monkey can not cross the river because the water runs too fast.
     (5)Neither of them can get the bananas.
     "Get on my back, I can carry you," the elephant says. When they arrive there,the monkey says,"Let me
 climb up."
     Now both of them get the bananas. They are eating the bananas. And they know they must help each
 other.
任務(wù)1: 根據(jù)短文內(nèi)容回答下列問題。
1. Why do they want to cross the river to the island?
    ______________________________________
2. Why can't the elephant get the bananas by himself?
    _________________________________
3. What do we learn from the story?
    ________________________________
任務(wù)2: 將文中劃線的句子翻譯成漢語。
4.                                                                  
5.                                                                  

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閱讀與表達(dá)。
     Eating in space is different from eating on Earth. The food that astronauts carry with them does not look
  like the food you eat.
     Some food is carried in closed bags. It is cooked and frozen (冷凍) before the astronauts get it. All the
  water is removed from the food. In the spaceship, the astronaut puts the water back. He "shoots" hot or
 cold water into the food bag with a special gun. He eats the food through a small hole in the bag. Other
 foods come in bite sizes. The astronaut puts a whole piece in his mouth at once. There can be no crumbs
 (碎屑). Crumbs would float (漂浮) around the spaceship and get in the way. Meat and cake often come
 in bite-size pieces.
     Astronauts cannot drink water from open cups. The water would float in drops in the air. The water is
  put in the special gun. The astronaut shoots the water into his mouth.
     Eating in space is not easy. Astronauts must learn to eat in their way.
1. What is the food carried in closed bags by astronauts like?
    ___________________________________________________________________.
2. How do the astronauts eat food in space?
    ___________________________________________________________________.
3. How do the astronauts drink water in space?
    ___________________________________________________________________.
4. Why can't the astronauts drink water from open cups?
    ___________________________________________________________________.
5. What is the main idea of the passage?
    _______________________________________________________________.

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