摘要:空军 the air force

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Under proper conditions,sound waves are reflected from a hillside or other such obstruction(障碍物).Sound travels at a speed of about one-fifth of a mile per second.If the hill is eleven hundred feet away,it takes two seconds for the sound to travel to the hill and back.Thus by measuring the time between a sound and its reflection the echo(回声),you can calculate(计算) the distance to an obstruction.?

During World WarⅡ the British made a practical use of this rule to discover German planes on their way to bomb(轰炸) London long before the enemy was near the object.They used radio waves instead of sound waves,since radio waves can pass through fog and clouds.The outnumbered Royal Air Force(RAF)(皇家空军) always seemed to be lying in wait at the right time and the puzzled Germans never to be surprised.It was radio echoes more than anything else that won the Battle of Britain.?

  Since the radio waves were used to tell the direction in which to send the RAF planes and the distance to send them[their range(距离范围) of flight,in other words],the device(装置) was called radio directing and ranging,and from the first letters the word radar(雷达) was formed.?

1.Sound waves reflected from a hill can be used to calculate the __________.?

A.speed of sound

B.time between a sound and its echo?

C.height of the hill

D.distance to the hill?

2.The British used radio waves because they__________ .?

A.were more exact than sound waves?

B.could not be discovered?

C.could pass through fog and clouds?

D.were easier to use than sound waves?

3.Practical use of radio waves brought about __________.?

A.new machines for planes?

B.a radio directing and ranging device?

C.new radio sets for RAF bombers?

D.a discovering device?

4.Radar allowed British to be able to__________ .?

A.discover German planes on their way to London?

B.direct the outnumbered RAF planes effectively?

C.kill German bomber pilots?

D.both A and B

5.The author of this passage mainly wanted to explain __________.

A.exactly how radar worked?

B.why the British used radio waves in their device?

C.how radar(word and device) came into being?

D.how radar helped the British win the battle??

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阅读理解

  Under proper conditions, sound waves are reflected from a hillside or other such obstruction

  (障碍物).Sound travels at a speed of about one-fifth of a mile per second.If the hill is eleven hundred feet away, it takes two seconds for the sound to travel to the hill and back.Thus by measuring the time between a sound and its reflection the echo(回声), you can calculate(计算)the distance to an obstruction.

  During World WarⅡ the British made a practical use of this rule to discover German planes on their way to bomb(轰炸)London long before the enemy was near the object.They used radio waves instead of sound waves, since radio waves can pass through fog and clouds.The outnumbered Royal Air Force(RAF)(皇家空军)always seemed to be lying in wait at the right time and the puzzled Germans never to be surprised.It was radio echoes more than anything else that won the Battle of Britain.

  Since the radio waves were used to tell the direction in which to send the RAF planes and the distance to send them[their range(距离范围)of flight, in other words], the device(装置)was called radio directing and ranging, and from the first letters the word radar(雷达)was formed.

(1)

Sound waves reflected from a hill can be used to calculate the _________.

[  ]

A.

speed of sound

B.

time between a sound and its echo

C.

height of the hill

D.

distance to the hill

(2)

The British used radio waves because they _________.

[  ]

A.

were more exact than sound waves

B.

could not be discovered

C.

could pass through fog and clouds

D.

were easier to use than sound waves

(3)

Practical use of radio waves brought about _________.

[  ]

A.

new machines for planes

B.

a radio directing and ranging device

C.

new radio sets for RAF bombers

D.

a discovering device

(4)

Radar allowed British to be able to _________.

[  ]

A.

discover German planes on their way to London

B.

direct the outnumbered RAF planes effectively

C.

kill German bomber pilots

D.

both A and B

(5)

The author of this passage mainly wanted to explain _________.

[  ]

A.

exactly how radar worked

B.

why the British used radio waves in their device

C.

how radar(word and device)came into being

D.

how radar helped the British win the battle

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A teddy bear from Cumbria is launching into space to raise cash for charity(慈善).

Terence, an experienced traveller who has been to Iraq, will be the guest of honour on aviation(航行) legend Burt Rutan’s Spaceship One when it flies above Earth. The mission takes off from California on September 29, and on his return the cuddly toy will be auctioned off(拍卖) in aid of the North Air Ambulance Appeal(北部空中救护服务中心).

Spaceship One is the world’s first private spacecraft, and is competing for a prestigious space travel prize. Chief executive of the Great North Air Ambulance Service (GNAAS), Graham Pickering, said “flying officer” Terence had been handed over to the RAF six months ago and staff had been receiving postcards from him ever since.

He said, “Terence was a fundraising idea that really took off. We have received pictures of him in a U2 craft, trying parachuting and even looking drunk and disorderly. When the RAF finally discharge him he will be a very rare bear indeed—we just hope he does not burn up on re-entry to Earth.”

GNAAS, which needs charitable donations of more than £2m a year, has three air ambulances(空中救护机).

Peter Bond, spokesman for the Royal Astronomical Society, said Terence’s safety was not guaranteed. He said, “This is a new and experimental craft and this will only be the second time it has flown. During its first voyage it developed technical problems but hopefully they have now been resolved.”

Since May, Terence has spent time with members of 100 Squadron(空军中队) based at RAF Leeming in Basra, Iraq, and at air shows with performing fighter planes.

Spaceship One will fly 100km (62 miles) above the Earth’s surface, just breaking through the planet’s atmosphere.

If it repeats the feat(技艺) inside two weeks, it will claim the $10m Ansari X-Prize set up to encourage the private space flight business.

Terence is ________.

A. a real bear living in England           B. an experienced astronaut

C. an air force officer                         D. a toy bear

We can infer that________.

A. after this space flight, Spaceship One will get the $10m Ansari X-Prize

B. it is dangerous for a spaceship to re-enter the earth atmosphere

C. Terence will be very safe on the flight

D. Spaceship One is just an ordinary plane

Which of the following is true of Spaceship One?

A. Spaceship One is the world’s first spacecraft.

B. The purpose of its flight is to collect money for the charity.

C. The purpose of its flight is to compete for a prestigious space travel prize.

D. Spaceship One has never flown.

Which of the following is the best title?

A. Teddy bear astronaut to lift off        B. Spaceship One to lift off

C. Space flight                                 D. The toy bear will be auctioned off

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A teddy bear from Cumbria is launching into space to raise cash for charity(慈善).
Terence, an experienced traveller who has been to Iraq, will be the guest of honour on aviation(航行) legend Burt Rutan’s Spaceship One when it flies above Earth. The mission takes off from California on September 29, and on his return the cuddly toy will be auctioned off(拍卖) in aid of the North Air Ambulance Appeal(北部空中救护服务中心).
Spaceship One is the world’s first private spacecraft, and is competing for a prestigious space travel prize. Chief executive of the Great North Air Ambulance Service (GNAAS), Graham Pickering, said “flying officer” Terence had been handed over to the RAF six months ago and staff had been receiving postcards from him ever since.
He said, “Terence was a fundraising idea that really took off. We have received pictures of him in a U2 craft, trying parachuting and even looking drunk and disorderly. When the RAF finally discharge him he will be a very rare bear indeed—we just hope he does not burn up on re-entry to Earth.”
GNAAS, which needs charitable donations of more than £2m a year, has three air ambulances(空中救护机).
Peter Bond, spokesman for the Royal Astronomical Society, said Terence’s safety was not guaranteed. He said, “This is a new and experimental craft and this will only be the second time it has flown. During its first voyage it developed technical problems but hopefully they have now been resolved.”
Since May, Terence has spent time with members of 100 Squadron(空军中队) based at RAF Leeming in Basra, Iraq, and at air shows with performing fighter planes.
Spaceship One will fly 100km (62 miles) above the Earth’s surface, just breaking through the planet’s atmosphere.
If it repeats the feat(技艺) inside two weeks, it will claim the $10m Ansari X-Prize set up to encourage the private space flight business.

  1. 1.

    Terence is ________.

    1. A.
      a real bear living in England
    2. B.
      an experienced astronaut
    3. C.
      an air force officer
    4. D.
      a toy bear
  2. 2.

    We can infer that________.

    1. A.
      after this space flight, Spaceship One will get the $10m Ansari X-Prize
    2. B.
      it is dangerous for a spaceship to re-enter the earth atmosphere
    3. C.
      Terence will be very safe on the flight
    4. D.
      Spaceship One is just an ordinary plane
  3. 3.

    Which of the following is true of Spaceship One?

    1. A.
      Spaceship One is the world’s first spacecraft.
    2. B.
      The purpose of its flight is to collect money for the charity.
    3. C.
      The purpose of its flight is to compete for a prestigious space travel prize.
    4. D.
      Spaceship One has never flown.
  4. 4.

    Which of the following is the best title?

    1. A.
      Teddy bear astronaut to lift off
    2. B.
      Spaceship One to lift off
    3. C.
      Space flight
    4. D.
      The toy bear will be auctioned off
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A teddy bear from Cumbria is launching into space to raise cash for charity(慈善)
Terence,an experienced traveller who has been to Iraq,will be the guest of honour on aviation(飞行)legend Burt Rutan’s Spaceship One when it flies above Earth.The mission takes off from California on September 29, and on his return the loveable toy will be auctioned off(拍卖)in aid of the North AIR Ambulance Appeal(北部空中救护服务中心).
Spaceship One is the world’s first private spacecraft,and is competing for a prestigious space travel prize.Chief executive of the Great North Air Ambulance Service (GNAAS),Graham Pickering,said”flying officer”Terence had been handed over to the RAF six months ago and staff had been receiving postcards from him ever since.
He said,“Terence was a fundraising idea that really took off. We have received pictures of him in a U2 craft,trying parachuting and even looking drunk and disorderly.When the RAF finally discharege him he will be a very rare bear indeed?--we just hope he does not bum up on re?entry to Earth”.
GNAAS,which needs charitable donations of more than £2m a year,has three air ambulances(空中救护机).
Peter Bond,spokesman for the Royal Astronimical Society,said Terence’s safety was not guaranteed. He said,“This is a new experimental craft and this will only be the second time it has flown.During its first voyage it developed technical problems but hopefully they have now been resolved.”
Since May,Terence has spent time with members of 100 squadron(空军中队)based at RAF Leeming Basra.Iraq,and at air shows with performing fighter planes.
Spaceship One will fly 100km(62 miles) above the Earth’s surface,just breaking through the planet’s atmosphere.
If it repeats the feat(技艺)inside two weeks,it will claim the $ 10 million Ansari X-Prize set up to encourage the private space flight business.
【小题1】Which of the following is the best title?

A.The Toy Bear Will Be Auctioned Off
B.Space Flight
C.Spaceship One to Lift Off
D.Teddy Bear Astronaut to Lift Off
【小题2】Terence is      .
A.an experienced astronaut
B.a toy bear
C.a real bear living in England
D.an air force officer
【小题3】Which of the following is true of Speaceship One?
A.Spaceship One is the world’s first speacecraft.
B.The purpose of its flight is to collect money for the charity.
C.The purpose of its flight is to comepete for a prestigious space travel prize.
D.Spaceship One has never flown.
【小题4】We can infer that      .
A.after this space flight,Spaceship One will get the $ 10 million Ansari X-prize
B.it is dangerous for a spaceship to re-entre the earth atmosphere
C.Terence will be very safe on the flight
D.Spaceship One is just an ordinary plane

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