When people first walked across the Bering Land Bridge thousands of years ago, dogs were by their sides, according to a study published in the journal Science.

When people first walked across the Bering Land Bridge thousands of years ago, dogs were by their sides, according to a study published in the journal Science.

　 Robert Wayne of the University of California, Los Angeles, and Jennifer Leonard of the Smithsonian Institute, used DNA material—some of it unearthed by miners in Alaska—to conclude that today’s domestic dog originated in Asia and accompanied the first humans to the New World about 10,000 to 15,000 years ago. Wayne suggests that man’s best friend may have enabled the tough journey from Asia into North America. “Dogs may have been the reason people made it across the land bridge,” said Wayne. “They can pull things, carry things, defend you from fierce animals, and they’re useful to eat.”

　 Dog remains from a Fairbanks-area gold mine helped the scientists reach their conclusion. Leonard, an evolutionary biologist, collected DNA from 11 bones of ancient dogs that were locked in permafrost(永冻层) until Fairbanks miners uncovered them in the 1920s. The miners donated the preserved bones to the American Museum of Natural History in New York City, where they remained untouched for more than 70 years. After borrowing the bones from the museum, Leonard and her colleagues used radiocarbon techniques to find the age of the Alaska dogs. They found the dogs all lived between the years of 1450 and 1675 A.D., before Vitus Bering and Aleksey Chirikov who were the first known Europeans to view Alaska in 1741. The bones of dogs that wandered the Fairbanks area centuries ago should therefore be the remains of “pure native American dogs,” Leonard said. The DNA of the Fairbanks dogs would also expose whether they were the descendents of wolves from North America.

　 Leonard and Wayne’s study suggests that dogs joined the first humans that made the adventure across the Bering Land Bridge to slowly populate the Americas. Wayne thinks the dogs that made the trip must have provided some excellent service to their human companions or they would not have been brought along. “Dogs must have been useful because they were expensive to keep,” Wayne said. “They didn’t feed on mice; they fed on meat, which was a very guarded resource.”

68. The first humans into the New World brought dogs along with them because dogs　　　　 .

　 A. kept people company B. were easy to stay alive

C. helped protect the supplies D. offered excellent service

69. The underlined word “remains” in Paragraph 3 probably refers to 　　　　　.

　 A. dead bodies B. animal waste　　 　 C. leftover food　 　　 D. living environment

70. According to the study described in Paragraph 3, we can learn that 　　　　　.

　 A. ancient dogs entered North America between 1450 and 1675 AD

　 B. the 11 bones of ancient dogs are not from native American dogs

　 C. the bones studied were not from dogs brought by Europeans

D. the bones found by the gold miners were from American wolves

71. The passage mainly talks about 　　　　　.

　 A. the DNA study of dogs in NorthAmerica 　

B. the origin of the North American dogs

C. why ancient people brought dogs to America 　

D. the difference between Asian and American dogs

When people first walked across the Bering Land Bridge thousands of years ago, dogs were by their sides, according to a study published in the journal Science.
Robert Wayne of the University of California, Los Angeles, and Jennifer Leonard of the Smithsonian Institute, used DNA material—some of it unearthed by miners in Alaska—to conclude that today’s domestic dog originated in Asia and accompanied the first humans to the New World about 10,000 to 15,000 years ago. Wayne suggests that man’s best friend may have enabled the tough journey from Asia into North America. “Dogs may have been the reason people made it across the land bridge,” said Wayne. “They can pull things, carry things, defend you from fierce animals, and they’re useful to eat.”
Researchers have agreed that today’s dog is the result of the domestication(驯化) of wolves thousands of years ago. Before this recent study, a common thought about the precise origin of North America’s domestic dog was that Natives domesticated local wolves, the descendents(后代) of which now live with people in Alaska, Canada, and the Lower 48.
Dog remains from a Fairbanks-area gold mine helped the scientists reach their conclusion. Leonard, an evolutionary biologist, collected DNA from 11 bones of ancient dogs that were locked in permafrost(永冻层) until Fairbanks miners uncovered them in the 1920s. The miners donated the preserved bones to the American Museum of Natural History in New York City, where they remained untouched for more than 70 years. After borrowing the bones from the museum, Leonard and her colleagues used radiocarbon techniques to find the age of the Alaska dogs. They found the dogs all lived between the years of 1450 and 1675 A.D., before Vitus Bering and Aleksey Chirikov who were the first known Europeans to view Alaska in 1741. The bones of dogs that wandered the Fairbanks area centuries ago should therefore be the remains of “pure native American dogs,” Leonard said. The DNA of the Fairbanks dogs would also expose whether they were the descendents of wolves from North America.
Along with the Fairbanks samples, the researchers collected DNA from bones of 37 dog specimens(标本) from Mexico, Peru, and Bolivia that existed before the arrival of Columbus. In the case of both the Alaska dogs and the dogs from Latin America, the researchers found that they shared the most genetic material with gray wolves of Europe and Asia. This supports the idea of domestic dogs entering the New World with the first human explorers who wandered east over the land bridge.
Leonard and Wayne’s study suggests that dogs joined the first humans that made the adventure across the Bering Land Bridge to slowly populate the Americas. Wayne thinks the dogs that made the trip must have provided some excellent service to their human companions or they would not have been brought along. “Dogs must have been useful because they were expensive to keep,” Wayne said. “They didn’t feed on mice; they fed on meat, which was a very guarded resource.”

1. 1.

   The underlined word “remains” is closed in meaning to ______

   1. A.
      leftover food
   2. B.
      animal waste
   3. C.
      dead bodies
   4. D.
      living environment
2. 2.

   According to the study described in Paragraph 4, we can learn that ______

   1. A.
      ancient dogs entered North America between 1450 and 1675 AD
   2. B.
      the 11 bones of ancient dogs are not from native American dogs
   3. C.
      the bones discovered by the gold miners were from North American wolves
   4. D.
      the bones studied were not from dogs brought into North America by Europeans
3. 3.

   What can we know from the passage?

   1. A.
      Native Americans domesticated local wolves into dogs
   2. B.
      Scientists discovered some ancient dog remains in 1920s
   3. C.
      Latin America’s dogs are different from North America’s in genes
   4. D.
      Ancient dogs entered North America across the Bering Land Bridge
4. 4.

   The first humans into the New World brought dogs along with them because ______

   1. A.
      dogs fed on mice
   2. B.
      dogs were easy to keep
   3. C.
      dogs helped protect their resources
   4. D.
      dogs could provide excellent service
5. 5.

   What does the passage mainly talk about ______

   1. A.
      the origin of the North American dogs
   2. B.
      the DNA study of ancient dogs in America
   3. C.
      the reasons why early people entered America
   4. D.
      the difference between Asian and American dogs

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BAIDU (www.baidu.com) is a daily miracle to millions of people. It is one of the most popular search engines on the web, a challenging competitor to Google! Type words, names of pictures or videos into the space given and in a second it can comp up with hundreds of related resources. Baidu leads to the entrance to the entrance to vast information.

A.  In 1993, “the father of NetEase” ( www.163.com )—Ding Lei wanted to make Internet-surfing easy for Chinese. At that time, most websites are run in English and only few in Chinese at a low speed but high price. To enable Chinese people remember this new website name, instead of English letter, he chose Arabia Number---“163.com”, which provides users with the largest e-mail and network hard disk.

B.  YAHOO( www.yahoo.com) was the first wonder of the web. It started in January 1994 by two students, but before the end of the year, it had become famous as Yahoo we know today.

C.  Taobao(www.taobao.com), which deals with companies online trading services, is one of the largest Internet companies where people buy and sell goods and services worldwide. It has opened up a global marker=place where the online service allows sellers or buyers to bargain.

D.  Gamedom(www.7k7k.com) started out as a fun world, offering a variety of games which suits people in different ages. It also does some business like selling popular computer games. Software. Or download hot music at a certain price.

E.  To meet the wordwide common belief-saving energy, news provided in electronic form is becoming necessary. News center (www.chinaenglish.com) can update the latest news daily and store old news. Pictures, comments, videos are offered as well.

1. Zhang Lin is always proud of being a Chinese and he never buys anything made in foreign countries. The net world set up by Chinese certainly is his favorite choice. Can you guess what will be his “e-mail address”?

2.Everybody knows that “Rome is not built in one day”, but what surprised Sam is that a famous website is setup by two students and become world=known within one year. Which web will he really admired most?

3.Li Lei has got an assignment from his teacher to write an essay. He’d like to surf the Internet to search for rich information. A search engine with fast speed and various resources will be of great help to him. Which web will he refer to?

4. Safeguard TianJun is lying in bed because of his brave fighting against several robbers. Being bored of reading books or sleeping, he borrowed a laptop to play computer games to relax himself and kill time. Which website suits his taste?

5.As a busy white-collar girl, Susan hardly has much time to go window shopping. But it no longer upsets her because during her working break, she can search for different goods online and even bargain. Where can she do this?

Santa Fe, the capital of New Mexico, U.S.A.,is in the central part of the state, on the Santa Fe River, which flows into the Rio Grande 35 kilometres west of the city. More than two thousand metres above sea level, it lies in the Sangre de Cristo Mountains with the Ortiz Mountains to the southeast.

Santa Fe was founded in 1609 by the Spanish (西班牙人)on an old Indian village.In 1680 the Indians seized the place but only held it for twelve years before the Spanish retook it. The city remained under Spanish rule until Mexico won its independence (独立) in 1821. From then on it was a Mexican city until 1846 when it was taken over by American troops.

With a population of 48,953, Santa Fe is now the second largest city in the state. Because of its sunny weather, rich history and surrounding mountains, it is a good place for holiday makers. Besides hunting and skating in the mountains people enjoy shopping in the Indian and Spanish shops, which brings a large income to the city every year. In summer there is an international opera (歌剧) season when operas are shown in a partly-roofed ,open-air theatre daily for people from all over the world.

1.At present Santa Fe belongs to            .

A. India           B. Mexico    C. Spain(西班牙)        D. the United States

2.Which of the drawings below gives an idea of what Santa Fe is like?

RG=the Rio Grande  SFR=the Santa Fe River  OM=the Ortiz Mountains

3.Santa Fe was under the rule of the Mexicans in         .

A. 1675                 B. 1695     C. 1816                D. 1833

4.One of the reasons for visitors to come to Santa Fe is that it             .

A. has fine weather

B. is the state capital

C. has historical monuments

D. is on the Santa Fe River