摘要: A. air B. steam C. wind D. ice

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Force other than damaging winds are also at work inside tornadoes. Sometimes, as the turning, jumping funnel(漏斗) passes over a house, the walls and ceiling burst apart as if a bomb had gone off inside. This explosion(爆炸) is caused by the low air pressure at the center of a tornado.

The pressure at the center of a tornado is usually 13 pounds per square inch. However, inside the house the air pressure is normal, about 15 pounds per square inch. The difference of 2 pounds per square inch between the inside and outside pressure may not seem like much. But suppose a tornado funnel passes over a small building that measures 20 by 10 by 10 feet. On each square inch of the building, there is 2 pounds of pressure from the inside that is not balanced by air pressure outside the building. On the ceiling, that adds up to an unbalanced pressure of 57,600 pounds. The pressure on the four walls adds up to 172,800 pounds.

If windows are open in the building, some of the inside air will rush out through them. This will balance the pressure inside and outside the building. But if the windows are shut tightly, the great inside pressure may cause the building to burst.

  Unfortunately, heavy rain happens in thunderstorms that later produce tornadoes. So, people often shut all windows to protect their property. This may cause far worse damage later.

63. Which of the following is the main topic of the passage?

A. Where tornadoes are formed.         B. When tornadoes usually occur.

C. How tornadoes can be prevented.       D. Why tornadoes cause so much damage.

64. According to the passage, tornadoes can destroy building because the _____.

A. force of a tornado increases the air pressure in a building

B. air pressure at the center of a tornado is over 172,000 pounds

C. weight of a tornado can crush a building’s roof when it passes overhead

D. air pressure inside a tornado is less than the air pressure inside a building

65. According to the passage, the pressure on a building during a tornado can be reduced    by _____.

A. closing the windows              B. opening the windows

C. using an electric fan               D. making the roof and walls stronger

 

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完形填空

  John is good swimmer. Every summer he goes to swim in the swimming pool nearby. He is 1 a good diver(跳水者). He learned to dive only several weeks ago. But he thought he had learned 2 and wanted to 3 his wife how much he had learned and how well he 4 dive.

  One day at three o'clock in the afternoon he drove his wife to the swimming pool, 5 her a place to sit 6 , made her very comfortable and then told her to 7 and watch 8 to dive.

  He climbed up the ladder and ran 9 the diving board to the end. He jumped high up 10 the air and turned a somersault(筋斗). But he 11 his head first on the board 12 a crash(撞击声). How 13 !

  Some people shouted for help. 14 people said it was silly 15 him to try that dive. His wife was very frightened. Soon John was taken to hospital and got 16 treatment(治疗). He was saved. The next 17 a report of John's 18 appeared in the newspaper. It began 19 this, “Yesterday afternoon, Mr. John Capp had a serious accident at the City Swimming Pool… 20 he was saved.”

1.

[  ]

A.also
B.not
C.such
D.neither

2.

[  ]

A.a little
B.little
C.a lot
D.lot

3.

[  ]

A.tell
B.show
C.employ
D.promise

4.

[  ]

A.should
B.would
C.might
D.could

5.

[  ]

A.kept
B.gave
C.found
D.left

6.

[  ]

A.on
B.by
C.about
D./

7.

[  ]

A.sit
B.come
C.wait
D.stand

8.

[  ]

A.her
B.him
C.them
D.people

9.

[  ]

A.along
B.from
C.across
D.through

10.

[  ]

A.on
B.above
C.from
D.in

11.

[  ]

A.jumped
B.hit
C.dropped.
D.landed

12.

[  ]

A.with
B.without
C.into
D.as

13.

[  ]

A.exciting
B.wonderful
C.adventurous
D.terrible

14.

[  ]

A.A few
B.Many
C.Other
D.Few

15.

[  ]

A.of
B.for
C.to
D.about

16.

[  ]

A.strange
B.kind
C.immediate
D.much

17.

[  ]

A.moment
B.hour
C.day
D.week

18.

[  ]

A.news
B.dive
C.treatment
D.accident

19.

[  ]

A.as
B.like
C.at
D.with

20.

[  ]

A.at least
B.how
C.however
D.but
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We were the only family with children in the restaurant. I sat Eric in a high chair and noticed everyone was quietly eating and talking. Suddenly, Eric screamed with 36 and said, “Hi there.” His fat baby hands hit the high chair tray, and his eyes were wide with excitement.

I looked around and saw the 37 of his enjoyment. It was an old man with a worn and oily coat. And his hair was uncombed and unwashed. I was sure he  38 . His hand waved. “Hi there, baby; I see ya,” the man said to Eric.

My husband and I 39  looks. Eric continued to laugh and answer, “Hi, there.” Everyone in the restaurant noticed this. My husband and I were embarrassed.

We finally got through the meal and  40   the door. My husband went to pay the check and told me to meet him in the parking lot. The old man sat between me and the door. “Lord, just let me out of here before he speaks to me or Eric,” I prayed. As I drew closer to the man, I turned my back trying to sidestep him and avoid any air he might be 41 . As I did so, Eric leaned over my arm, reaching with both arms in a baby's “pick-me-up” position. Before I could stop him, he had  42 himself to the man's arms.Eric, in an act of total 43 , and love, laid his tiny head upon the man's torn shoulder.

His  44  hands full of dirt, pain and hard labor gently, so gently, cradled my baby's waist and patted his back. I stood amazed. After a while, he pushed Eric from his chest 45 as though he were in pain, saying “God bless you, ma'am. You've given me the best Christmas gift.”

I had just witnessed a genuine (pure or true) love shown through the innocence of a tiny child who saw no sin, who made no 46 . The ragged old man, unknowingly, had reminded me that a genuine love is one in which the true meaning of love is 47 .

36. A. surprise    B. delight    C. anger        D. nerve

37. A. source         B. reason    C. effect        D. resource

38. A. smiled      B. mopped   C. smelled      D. wiped

39. A. consulted   B. exchanged  C. separated     D. replaced

40. A. ran for    B. headed for    C. sent for     D. accounted for

41. A. breathing   B. fighting     C. creating     D. holding

42. A. thrown      B. devoted     C. driven        D. jumped

43. A. independence    B. desire    C. trust       D. dignity

44. A. allergic    B. strong      C. smart       D. aged

45. A. eagerly    B. violently   C. gladly         D. unwillingly

46. A. judgment     B. decision   C. conclusion      D. choice

47. A. sharpened     B refreshed     C. realized        D. learned

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