boundary A. curious B. trouble C. house D. ought 查看更多

 

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Everyone has heard of the San Andreas fault (断层), which constantly threatens California and the West Coast with earthquakes. But how many people know about the equally serious New Madrid fault in Missouri?

   Between December of 1811 and February of 1812, three major earthquakes occurred, all centered around the town of New Madrid, Missouri, on the Mississippi River. Property damage was severe. Buildings in the area were almost destroyed. Whole forests fell at once, and huge cracks opened in the ground,  releasing some strong smell chemicals.

   The Mississippi River itself completely changed character, developing sudden rapids and whirlpools (激流和漩涡). Several times it changed its course, and once, according to some observers, it actually appeared to run backwards. Few people were killed in the New Marid earthquakes, probably simply because few people lived in the area in 1811; but the severity of the earthquakes are shown by the fact that the shock waves rang bells in church towers in Charleston, South Carolina, on the coast. Buildings shook in New York City, and clocks were stopped in Washington, D.C.

Scientists now know that America's two major faults are essentially different. The San Andreas is a horizontal boundary between two major land masses that are slowly moving in opposite directions. California earthquakes result when the two masses make a sudden move.

     The New Madrid fault, on the other hand, is a vertical fault; at some points, possibly hundreds of millions of years ago, rock was pushed up toward the surface, probably by volcanoes under the surface. Suddenly, the volcanoes cooled and the rock collapsed, leaving huge cracks. Even now, the rock continues to settle downwards, and sudden sinking motions cause earthquakes in the region. The fault itself, a large crack in this layer of rock, with dozens of other cracks that split off from it, extends from northeast Arkansas through Missouri and into southern Illinois.

   Scientists who have studied the New Madrid fault say there have been numerous smaller quakes in the area since 1811; these smaller quakes indicate that larger ones are probably coming, but the scientists say they have no method of predicting when a large earthquake will occur.

1.This passage is mainly about ___________.

A. current scientific knowledge about faults

B. the San Andreas and the New Madrid faults

C. the causes of faults        

D. the New Madrid fault in Missouri

2.The New Madrid fault is __________.

A. a vertical fault

B. a horizontal fault

C. a more serious fault than the San Andreas fault

D. responsible for forming the Mississippi River

3.This passage implies that _________.      .

A. horizontal faults are more dangerous than vertical faults

B. Vertical faults are more dangerous than horizontal faults

C. The volcanoes that caused the New Madrid fault are still alive

D. A lot of people would die if the 1811 New Madrid earthquakes happened today

 

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阅读理解

  Every living thing has a physical boundary(分界线) that separated it from its external environment. Beginning with the bacteria and the simple cell and ending with man, every organism has a certain limit which marks where it begins and ends.

  Anyone who has had experience with dogs, particularly in the countryside such as on farms, is familiar with the way in which the dog handles space. In the first place, the dog knows the limits of his aster's yard and will defend it against encroachment. There are also certain places where he steeps: a spot next to the fireplace, a spot in the kitchen, or one in the dinning room if he is allowed there. In short a dog has fixed points to which he returns time after time depending upon the occasion. One can also observe that the dog creates zone he is in, a trespasser(非法进入者) can cause different behaviours when he crosses the invisible lines which are meaningful to the dog.

  This is particularly noticeable in females with pup-pies. A mother who has a new litter(一胎所生的小动物) in a little-used barn wall claim the barn as her territory. When the door opens she may make a slight movement or stir in one corner. Nothing else may happen as the intruder moves ten or fifteen feet into the barn. Then the dog may raise her head or get up circle about and lie down as another visible boundary is crossed. One can tell about where the line is by withdrawing and watching when her head goes down. As additional lines are crossed, there will be other signals, a thumping(重击) of the tail, a low moan or a growl. One can also observe comparable behavior in other vertebrates(脊椎动物)-fish, birds and mammals.

1.A dog on a farm knows ________.

[  ]

A.the size of its master's yard

B.the only fixed place where it should sleep

C.it should not sleep in the kitchen

D.the area that it should defend

2.A female dog with puppies will probably ________.

[  ]

A.attack any stranger who comes near

B.signal differently according to different occasions

C.raise her head at the sight of a stranger

D.growl when a stranger leaves her territory

3.It can be inferred from the third paragraph that mother dogs ________.

[  ]

A.have a sense of gradual territory

B.protect their babies cautiously

C.are ready to attack strangers

D.prefer to raise babies in barns

4.In the second paragraph, the underlined word “encroachment” probably means ________.

[  ]

A.aggression
B.attack
C.aggressors
D.trespasser

5.Which of the following is FALSE according to the passage?

[  ]

A.Dogs sleep at certain places in the yard or house.

B.logs will respond to territory trespasser.

C.The boundary lines are visible and meaningful to dogs.

D.Fish, birds belong to vertebrates.

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Loving France

Landing in France, a sacred feeling suddenly arises which attracts you to know more about this country.  

France, about hexagonal (六边形) in shape, has a boundary on the east with Germany, Switzerland and Italy, and is bounded on the southeast by Monaco and the Mediterranean Sea; on the south are Spain and Andorra, with the Bay of Biscay on the west and the English Channel on the north as natural borders.

A series of massive mountain ranges includes the Alps, which separate France and Italy, and the Jura Mountains that delineate (画出轮廓) the Franco-Swiss border. The Rhine River, at the northeast corner of France forms the Franco-German boundary. The Pyrenees Mountains, extending along the Franco-Spanish frontier from the Mediterranean to the Bay of Biscay, forms the other mountain boundary of France.

  The plains region is a projection of the great plain of Europe. The outstanding features of the plains are the river valleys. Among all the rivers, totaling more than 200 with numerous tributaries which are almost all commercially navigable, the Rhine River is the largest in terms of discharge volume.

  The capital and largest city in France is Paris, which attracts many visitors every year. Marseilles is a chief port and Lyon is an industrial center famous for its textiles. Other major cities include Toulouse, an industrial and trade center; Nice, a resort; Strasbourg, a Rhine River port and industrial and commercial center; Bordeaux, a seaport and most famous for its wine.   

French perfume, champagne, and bridges in Paris… want to know more? Then next time we will return to Paris, and you will learn more about her.

1.How many mountain ranges are mentioned in the passage?

A. 2    B. 3    C. 4     D. 5

2.The underlined word “discharge” means ______.

  A. storage   B. electric power production   C. the release of water  D. the money made

3.Which is not TRUE according to the passage?

A. Spain is to the southwest of Germany.

B. Mountains are the outstanding features of the plains.

C. Both Marseilles and Bordeaux are ports.

D. Both Nice and Paris attract many tourists every year.

4.Which city is flourishing both in its industry and commerce?

A. Marseilles  B. Lyon  C. Toulouse   D. Strasbourg

 

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The researchers, led by Hwang Woo-suk, insist they cloned an Afghan hound, only to help investigate (研究) human disease, including the possibility of cloning stem cells (干细胞) for treatment purposes.

But others immediately renewed calls for a global ban on human reproductive cloning before the technology moves any farther.

“Successful cloning of an increasing number of species confirms the general impression that it would be possible to clone any species of mammals, including humans,” said Ian Wilmut, a reproductive biologist at the University of Edinburgh who produced the first cloned mammal, Dolly the sheep, from an adult cell nearly a decade ago.

Researchers have since cloned cats, goats, cows, mice, pigs, rabbits, horses, deer, mules and gaur, a large wild ox of Southeast Asia. So far, efforts to clone a monkey or another primate with the same techniques have failed.

Uncertainties about the health and life span (寿命) of cloned animals continue to exsist; Dolly died at a young age in 2003 after developing cancer and arthritis.

Wilmut and others complimented Hwang’s achievement, reported Wednesday in the journal Nature. But they said politicians and scientists must face the larger issue — how to go on with the research without crossing the moral boundary of copying human life in the lab.

“The ability to use the technology is hopeful,” said Robert Schenken, president of the American Society for Reproductive Medicine. “However, the paper also points out that in dogs as in most species, cloning for reproductive purposes is unsafe.”

The cloned puppy was the lone success from more than 100 dogs implanted (嵌入)with more than 1,000 cloned embryos.

In a news conference in Seoul, the cloning team also condemned the reproductive cloning of humans as “unsafe and inefficient.” Human reproductive cloning already is banned in South Korea. Other nations, including the United States, are divided on whether to ban just human cloning or cloning of all kinds, including the production of stem cells.

43. An Afghan hound is a kind of ______.

  A. cat              B. dog          C. cow         D. goat

44. A ______ is a large wild ox of Southeast Asia.

  A. horse        B. deer      C. mules    D. gaur

45.Accrding to the passage, scientists haven’t been able to clone a ______ so far.

  A. deer      B. mule     C. monkey     D. mouse

46.The underlined word complimented is probably similar in meaning to ______.

  A. praised      B. doubted   C. refused     D. gave up

47.The cloning of human beings is banned in ______.

  A. South Korea              

B. the United States

C. both South Korea and the United States 

D. neither South Korea nor the United States

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By international agreement the boundary of each nation ________ a body of water extends exactly three miles from the coastline.

[  ]

A.look
B.faced
C.to face
D.fronting

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