题目内容

A tornado is a r__________ column of air from a thunderstorm to the ground.

 

rotating

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When a tornado touched down in a small town nearby, many families were left completely destroyed. Afterward all the local newspapers carried many human-interest stories featuring some of the families who suffered the hardest.
One Sunday, a particular picture especially touched me. A young woman stood in front of an entirely shattered mobile home, a depressed expression twisting her features. A young boy, seven or eight years old, stood at her side, eyes downcast. Clutching  (紧握)  at her skirt was a tiny girl who stared into the camera, eyes wide with confusion and fear.
The article that went with the picture gave the clothing sizes of each family member. With growing interest, I noticed that their sizes closely matched ours. This would be a good opportunity to teach my children to help those less fortunate than themselves. I taped the picture of the young family to our refrigerator, explaining their difficulty to my seven-year-old twins, Brad and Brett, and to three- year-old Meghan.
“ We have so much. And these poor people now have nothing,” I said.“We’ll share what we have with them.”
I brought three large boxes down from the room upstairs and placed them on the living room floor. Meghan watched seriously, as the boys and I filled one of the boxes with canned goods and foods.
While I sorted through our clothes, I encouraged the boys to go through their toys and donate some of their less favorite things. Meghan watched quietly as the boys piled up discarded toys and games.
“I’ll help you find something for the little girl when I’m done with this,” I said.
The boys placed the toys they had chosen to donate into one of the boxes while I filled the third box with clothes. Meghan walked up with Lucy, her worn, faded, much-loved rag doll hugged tightly to her chest. She paused in front of the box that held the toys, pressed her round little face into Lucy’s flat, painted-on-face, gave her a final kiss, then laid her gently on top of the other toys.
“Oh, Honey,” I said.“You don’t have to give Lucy. You love her so much.”
Meghan nodded seriously, eyes glistening with held-back tears. ‘”Lucy makes me happy, Mommy. Maybe she’ll make that other little girl happy, too．”
Swallowing hard, I stared at Meghan for a long moment, wondering how I could teach the boys the lesson she had just taught me. For I suddenly realized that anyone can give their cast-offs away. True generosity is giving that which you value most.
Honest benevolence  (善行)  is a three-year-old offering a valuable, though shabby, doll to a little girl she doesn’t know with the hope that it will bring this child as much pleasure as it brought her. I, who had wanted to teach, had been taught.
The boys had watched, open-mouthed, as their baby sister placed her favorite doll in the box. Without a word, Brad rose and went to his room. He came back carrying one of his favorite action figures. He hesitated briefly, clutching the toy, then looked over at Meghan and placed it in the box next to Lucy.
A slow smile spread across Brett’s face. Then he jumped up, eyes twinkling as he ran to fetch some of his prized Matchbox cars.
Astonished, I realized that the boys had also recognized what little Meghan’s gesture meant. Swallowing back tears, I pulled all three of them into my arms.
Taking the cue from my little one, I removed my old jacket from the box of clothes. I replaced it with the new hunter green jacket that I had found on sale last week. I hoped the young woman in the picture would love it as much as I did.
It’s easy to give that which we don’t want any more, but harder to let go of things we cherish, isn’t it? However, the true spirit of giving is to give with your heart..
【小题1】Why does the author give a detailed description of a particular picture in the Sunday newspaper?

A．To create an atmosphere of fear and depression brought by the tornado.
B．To appeal to unconcerned people to donate for the poor families.
C．To show the helplessness and hopelessness of the family mentioned in the paper.
D．To stress what touched her and made her decide to help the hopeless family.
【小题2】Why did Brad and Brett also donate their favorite things finally?
A．They were encouraged to donate some valuable things by the mother.
B．Meghan’s decision inspired them to donate their favorite things.
C．They also wanted to show generosity by giving away their valuable things.
D．Meghan’s gesture reminded them to replace their favorite things with new ones.
【小题3】By “ swallowing hard”, the writer means that   _   _ .
A．she was deeply puzzled by what the little girl did
B．she had trouble persuading Meghan not to give away Lucy
C．she was greatly moved by Meghan’s unexpected decision
D．she was uncertain what consequences Meghan’s action would bring about
【小题4】It is suggested in the sentence “the true spirit of giving is to give with your heart” that ______.
A．sincere donation means offering help to others whole-heartedly
B．true giving means giving others what you treasure most
C．true generosity means helping others at the cost of your own benefit
D．honest benevolence means devoting yourself to the career of donation
【小题5】What’s the best title for this passage?
A．The Greatest LoveB．A Beautiful Heart
C．True GenerosityD．A Precious Gift

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

Ever wonder how much a cloud weighs? What about a hurricane? A meteorologist has done some estimates and the results might surprise you.

Let's start with a very simple white puffy cloud — a cumulus cloud（积云）. How much does the water in a cumulus cloud weigh? Peggy LeMone, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, did the numbers. "The water in the little cloud weighs about 550 tons," she calculates. "Or if you want to convert it to something that might be a little more meaningful … think of elephants."

The thought of a hundred elephants-worth of water suspended in the sky begs another question — what keeps it up there?

"First of all, the water isn't in elephant sized particles（微粒）, it's in tiny tiny tiny particles," explains LeMone. And those particles float on the warmer air that's rising below. But still, the concept of so much water floating in the sky was surprising even to a meteorologist like LeMone. "I had no idea how much a cloud would weigh, actually, when I started the calculations," she says.

So how many elephant units of water are inside a big storm cloud—10 times bigger all the way around than the "puffy" cumulus cloud? Again, LeMone did the numbers: About 200,000 elephants.

Now, ratchet up the calculations for a hurricane about the size of Missouri and the figures get really massive. "What we're doing is weighing the water in one cubic meter theoretically pulled from a cloud and then multiplying by the number of meters in a whole hurricane," she explains.

The result? Forty million elephants. That means the water in one hurricane weighs more than all the elephants on the planet. Perhaps even more than all the elephants that have ever lived on the planet.

1.The weight of      is NOT mentioned in the passage.

A．a cumulus cloud    B．a tornado          C．a hurricane        D．a storm cloud

2.How did Peggy LeMone feel about the result of her calculations?

A．She found it not convincing.

B．She thought it needed further calculations.

C．She was quite surprised at it.

D．She considered the calculations inaccurate.

3.What can be inferred from the passage?

A．A storm cloud weighs about 200,000 elephants.

B．The water in a hurricane weighs more than that in any other kind of cloud.

C．There are less than forty million elephants living on the earth.

D．The water in the cloud is in very tiny partials.

 

Hurricane(飓风) reached the northeastern United States today and caused death and destruction everywhere. The killer storm carried winds of 135 miles per hour. The high winds and heavy rains created extremely dangerous waves. It is not yet known how many people died or were hurt in this storm, but it is said that the numbers will be very high.

With the arrival of the tornado season, the National Weather Service is again telling people how to protect themselves from these deadly storms. The winds from tornadoes are the most violent winds on earth. They can blow up to 400 miles per hour. A tornado looks like a funnel(漏斗). It is also very loud. It may sound like a train coming at you. In fact, the winds from a tornado can pick up a train and throw it around. If a tornado is seen in your area, it is very important that you protect yourself. A basement (地下室) is the safest place to go. Try to wait under a table in the basement. Stay away from windows. If you are outside or in your car, try to find a narrow place to hide.

As the area tries to deal with the worst flood of the century, there are many heartwarming stories of people helping other people. From all over the world people have sent food and clothes to help the thousands who have had to leave their homes. Many volunteers have come to help to make sandbags and use them to build walls against the overflowing river. While the result of this disaster will be terrible for many, it is beautiful to see people coming together to help others and save lives.

1.What does the underlined word “tornado” mean?

A．台风

B．龙卷风

C．洪水

D．冰雹

2.Which of the following is WRONG about tornados?

A．They look like a funnel.

B．They come regularly every year.

C．They are the most violent winds on Earth.

D．They carry winds of 135 km per hour.

3.According to the passage, a person who sees a tornado in his area had better NOT ______.

A．drive his car away as fast as possible

B．go to the basement and wait under a table

C．find a narrow place to hide

D．stay away from windows

4.We can learn from the passages that ______.

A．nobody tried to help the local people

B．hurricane damaged the northwestern coast of US

C．when there is flooding, sandbags can be made and used to build walls

D．people are often taught how to protect themselves from snowstorms

 

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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