Why did humans evolve to walk upright? Perhaps it’s just plain easier. Make that “energetically less costly”, scientifically speaking.

       Bipedalism—walking on two feet, is one of the defining characteristics of being humans, and scientists have debated for years how it came about. In the latest attempt to find an explanation, researchers trained five chimps (黑猩猩) to walk on a treadmill (跑步機) while wearing masks that allowed measurement of their oxygen consumption. The chimps were measured both while walking upright and while moving on their legs and knuckles (關(guān)節(jié)). That measurement of the energy needed to move around was compared with similar tests on humans and the results are published in this week’s online edition of “Proceedings of the National Academy of Sciences.

       It turns out that humans walking on two legs use only one-quarter of the energy that chimps use while knuckle-walking on four limbs(肢). And the chimps, on average, use as much energy using two legs as they did when they used all four limbs.

       However, there were differences among chimps in how much energy they used, and this difference corresponded to their different manner of walking and anatomy (解剖構(gòu)造). One of the chimps used less energy on two legs, one used about the same and the others used more, said David Raichlen, assistant professor of anthropology at the University of Arizona.

       “What we were surprised at was the variation,” he said in a telephone interview. “That was pretty exciting, because when you talk about how evolution works, variation is the bottom line, without variation there is no evolution.”

       Walking on two legs freed our arms, opening the door to drive the world, said Raichlen. “We think about the evolution of bipedalism as one of first events that led hominids (原始人) down the path to being humans.

       The research was supported by the National Science Foundation and the L. S. B. Leakey Foundation.

1. The underlined word “Bipedalism” in Paragraph 2 probably means ________.

       A. moving sideways                    B. walking upright               

C. walking on four legs                D. running fast

2. We can infer from the passage that_________.

       A. scientists have no idea on how humans’ walking on two legs came about

       B. scientists have had different views on why chimps walk on four legs

       C. scientists have had different views on how humans’ walking on two legs came about

       D. scientists have had similar views on how humans’ walking on two legs came about

3. What is Paragraph 4 mainly about?

       A. How chimps saved energy.

       B. Why chimps didn’t walk on two legs.

       C. David Raichlen studies chimps.

       D. Different chimps consumed different energy.

4. According to the passage, humans walk upright in order to ________.

       A. conserve energy                      B. differ from other animals

       C. free their brains                       D. strengthen their legs

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What is the hottest topic at your school recently? In Hangzhou Yongjin Middle School, it’s money. The school held an activity called “making money” last weekend. About 200 students of Senior 1 and Senior 2 were divided into 30 teams. They went out to make money by selling things. What did they choose to sell? Some sold newspapers; some chose bottled water; some sold environmentally friendly shopping bags and bamboo(竹子) baskets.
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C．About 200 students of the three gradesD．Part of Junior 1 and Junior 2 students
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B．the Children Activity Center was too crowded
C．the officers didn’t allow them to sell anything there
D．the team played the game of the hide-and-seek the whole morning
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A．The team put up a magic board.B．A foreigner came up and helped them.
C．The people liked to help country kids.
D．The people were interested in their ice cream.
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B．it’s not easy for their parents to make money
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The company's February China sales rose 30 percent to 45,400 vehicles, underperforming the overall passenger-car.

1.According to the passage, why did Toyota carmaker recall their cars in China last month? _____________

A．Because it faced law suits in the US

B．Because there were problems with the cars.

C．Because of the importance of the Chinese market

D．Because the customers are not satisfied with the charging of a 5,000 Yuan premium.

2.What does the underlined phrase“take the initiative” mean?

A．took the advice

B．changed his mind

C．took the action

D．made the decision

3.Why did Toyota president Akio Toyota skip Europe’s Geneva auto show?

A．Because he did not think it important

B．Because he was not satisfied with the hearing in the US

C．Because he attached importance to the Chinese Market

D．Because he needed to make an apology to Chinese

4.After the global recalls of millions vehicles, Toyota will be impacted in the following aspects, EXCEPT_________.

A．Its brand will be damaged

B．Its profit margins will shrink

C．It will have to face law suits

D．The president will be fired

5.Where can read the passage? __________

A．newspaper

B．magazine

C．encyclopedia

D．a(chǎn) school book

 

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What is the hottest topic at your school recently? In Hangzhou Yongjin Middle School, it’s money. The school held an activity called “making money” last weekend. About 200 students of Senior 1 and Senior 2 were divided into 30 teams. They went out to make money by selling things. What did they choose to sell? Some sold newspapers; some chose bottled water; some sold environmentally friendly shopping bags and bamboo(竹子) baskets.

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86. 1.In Hangzhou Yongjin Middle School, what the students talk more about is ________.

A．the officers

B．the kind foreigner

C．the activity called “making money”

D．the money they made last weekend

87. 2.________ took part in the activity.

A．All the students

B．Some teachers

C．About 200 students of the three grades

D．Part of Junior 1 and Junior 2 students

88. 3. Hu Qing’s team finally gave up because ________.

A．the parents didn’t like to buy the books

B．the Children Activity Center was too crowded

C．the officers didn’t allow them to sell anything there

D．the team played the game of the hide-and-seek the whole morning

89. 4.Why did more people come to Wang Bing’s stall at last?

A．The team put up a magic board.

B．A foreigner came up and helped them.

C．The people liked to help country kids.

D．The people were interested in their ice cream.

90. 5. According to the passage the students learn ________.

A．it’s impossible for them to make money

B．it’s not easy for their parents to make money

C．it’s very important for them to make a living

D．it’s necessary for school to hold more activities in the future

 

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