题目内容
year.
B. cut up
C. cut off
D. cut out
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浙江之星学业水平测试系列答案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. The underlined word “remains” is closed in meaning to ______.
A. leftover food B. animal waste
C. dead bodies D. living environment
2. According to the study described in Paragraph 4, 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 discovered by the gold miners were from North American wolves
D. the bones studied were not from dogs brought into North America by Europeans
3. What can we know from the passage?
A. Native Americans domesticated local wolves into dogs.
B. Scientists discovered some ancient dog remains in 1920s.
C. Latin America’s dogs are different from North America’s in genes.
D. Ancient dogs entered North America across the Bering Land Bridge.
4. The first humans into the New World brought dogs along with them because ______.
A. dogs fed on mice B. dogs were easy to keep
C. dogs helped protect their resources D. dogs could provide excellent service
5.What does the passage mainly talk about ______.
A. the origin of the North American dogs
B. the DNA study of ancient dogs in America
C. the reasons why early people entered America
D. the difference between Asian and American dogs
Count Me Out
Call me old-fashioned. Call me old. Call me what you want, but I refuse to become part of this new Internet world.
I do not possess a computer at home or at the office. Actually, I stopped going to an office 35 years ago, when all communications were done with a pen, a typewriter, or, if the matter was of world-shaking importance, over the telephone. Likewise, if you like something advertised in a newspaper or magazine, you visited the shop selling it at the given address, or you phoned the number shown. Then you spoke to the fellow and asked for further details.
Tell me what you think of the following ad that appeared the other day in the newspaper. It was for a cure for cancer and this is what it said: “Awareness is the key. Visit spfulford. com at the awareness site.” There was no address or telephone number for the site. So what do unfortunate people without a computer do if they are seeking a cure for their illness?
There are, I am told, certain advantages in having access to the Internet. You can, for example, send love messages across the world or even get married to someone that you meet online. This bit doesn’t interest me; I have been happily married for 60 years. There are, of course, other activities for Internet users besides finding love. They can pay bills, order groceries, or discuss with their doctors.
And this is by no means all. More amazing things are yet to come in the near future. I read a newspaper report recently that quoted Stephen Hawking, an important British scientist. “The complexity of a computer as it exists today is probably less than the brain of an earthworm,” he said. “But, as technology advances, computers will become more complex, and a time may come when the Internet may develop ‘consciousness.’ In other words, the Internet will be able to think, have feelings, and may well be able to act on its own.”
If Professor Hawking is right, I may change my attitude to computers. As I grow older each day, I would like one of those that not only thinks for me but also accepts responsibilities for all my mistakes.
1.
What’s the meaning of the title “Count Me Out”?
|
A．Get me out of the Internet world. |
|
B．Computers are trying to take control of life. |
|
C．Modern technology pushes old people away. |
|
D．Do not expect me to be a supporter of the Internet. |
2.
According to Paragraph 2, the author thinks computers are .
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A．unnecessary |
B．convenient |
C．expensive |
D．advanced |
3.
What might the author like about the future computer?
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A．Taking blames. |
B．Curing illnesses. |
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C．Delivering messages. |
D．Responding to emotions. |