Why did humans evolve to walk upright? Perhaps because 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(跑步机)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(膝关节).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 knucklewalking 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(解剖构造).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(变异) ”, he said in a telephone interview. 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. The underlined word “Bipedalism” in Paragraph 2 probably means____.
| A．moving sideways | B．walking upright |
| C．walking on four legs | D．running fast |
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 vame about |
| D．scientists have had similar views on how humans’ walking on two legs came about |
What is Paragraph 4 mainly about?
| A．How chimps saved energy. |
| B．Why chimps didn't walk on two legs. |
| C．David Raichlen studied chimps. |
| D．Different chimps consumed different energy. |
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 |
(2014 河北开滦月考) I came to study in the United States a year ago. Yet I did not know the real American society until I was injured in a car accident because after the accident I had to see a doctor and go to court.
After the accident, my roommate called a doctor for me. I was very grateful and determined to repay him one day. But the next day, he asked me to pay him $200 for what he had done. I was astonished. He had good reason to charge me, he said. And if I wanted to collect money from the person who was responsible for my injury, I'd have to have a good lawyer. And only a good doctor can help me get a good lawyer. Now that he had helped me find a good doctor, it was only fair that I should pay him.
But every day I went to see the doctor, I had to wait about 50 minutes. He would see two or three patients at the same time, and often stop treating one so as to see another. Yet he charged me $115 each time. The final examination report consisted of ten lines, and it cost me $215.
My lawyer was all smiles the first time we met. But after that he avoided seeing me at all. He knew very well the other party was responsible for the accident, yet he hardly did anything. He simply waited to collect his money. He was so irresponsible that I decided to dismiss him. And he made me pay him $770.
Now I had to act as my own lawyer. Due to my inexperience, I told the insurance company the date I was leaving America. Knowing that, they played for time... and I left without getting a cent.The author's roommate offered to help him because __________.
| A．he felt sorry for the author |
| B．he thought it was a chance to make some money |
| C．he knew the doctor was a very good one |
| D．he wanted the author to have a good lawyer |
A good doctor is essential (必要) for the author to __________.
| A．be properly treated |
| B．talk with the person responsible for the accident |
| C．recover before he leaves America |
| D．eventually get the responsible party to pay for his injury |
The word "charge" in the second paragraph means __________.
| A．be responsible | B．accuse |
| C．ask as a price | D．claim |
Both the doctor and the lawyer in this passage are very __________.
| A．selfish | B．friendly | C．professional | D．busy |
What conclusion (结论) can you draw from the story?
| A．Going to court is something very common in America. |
| B．One must be very careful while driving a car. |
| C．There are more bad sides in America than good sides. |
| D．Money is more important than other things in the US. |
A small town in southwest Britain is banning plastic bags in an attempt to help the environment and cut waste—a step that environmentalists believe is a first for Europe.
Shopkeepers in Modbury, population 1, 5000, agreed to stop handing out disposable plastic bags to customers on Saturday. They said paper sacks and cloth carrier bags would be offered instead.
Last month, San Francisco became the first U. S. city to ban plastic grocery bags. Internationally, laws to discourage the use of plastic bags have been passed in parts of South Africa and Ireland, where governments tax shoppers who use them or fine companies that hand them out. Bangladesh already bans them, and so do at least 30 remote Alaskan villages.
Modbury, about 225 miles southwest of London， has also declared a bag amnesty (宽限期), allowing local people to hand in plastic bags that have piled up at home. They will be sent for a recycling.
The Modbury ban was the idea of Rebecca Hosking, who saw the effect of bags on wildlife while working in the Pacific as a wildlife camerawoman. She said response in the town so far had been "really positive".
"Modbury is quite an old-fashioned town and a lot of people have wicker (柳条)baskets to go out shopping anyway," Hosking told Sky News Television.
The Worldwatch Institute, an environmental research agency， states that 100 billion plastic bags are thrown away each year in the United States alone. More than 500 billion are used yearly around the world. What was Rebecca Hosking?
| A．A lawyer. | B．An environmentalist. |
| C．A sailor. | D．A photographer. |
The underlined word "disposable" in Paragraph 2 probably means ______.
| A．acceptable | B．valuable |
| C．throw-away | D．long-lasting |
It can be inferred from the passage that ______ .
| A．most of the people in Modbury continue to use plastic bags |
| B．fewer and fewer plastic bags will be used in the world |
| C．San Francisco is the first city to ban plastic bags in the world |
| D．most countries in the world have passed laws to ban plastic bags |
Which of the following would be the best title of the passage?
| A．Environment |
| B．Cutting Waste |
| C．Effect of Plastic Bags |
| D．A British Town Banning Plastic Bags |
Every people has its own way of saying things, its own special expressions. Many everyday American expressions are on colors.
Red is a hot color. Americans often use it to express heat. They may say they are red hot about something unfair. When they are red hot，they are very angry about something. The small hot tasting peppers found in many Mexican foods are called red hots for their color and their fiery taste. Fast loud music is popular with many people. They may say the music is red hot, especially the kind called Dixieland jazz.
Pink is a lighter kind of red. People sometimes say they are in the pink when they are in good health. The expression was first used in America at the beginning of the twentieth century. It probably comes from the fact that many babies are born with a nice pink color that shows that they are in good health.
Blue is a cool color. The traditional blues music in the United States is the opposite of red hot music. Blues is slow, sad and soulful. Duke Ellington and his orchestra recorded a famous song Mood Indigo about the deep blue color, indigo. In the words of the song: "You ain't been blue till you've had that Mood Indigo." Someone who is blue is very sad.
The color green is natural for trees and grass. But it is an unnatural color for humans. A person who has a sick feeling stomach may say she feels a little green. A passenger on a boat who is feeling very sick from high waves may look very green.
Sometimes a person may be upset because he does not have something as nice as a friend has, like a fast new car. That person may say he is green with envy. Some people are green with envy because a friend has more dollars or greenbacks. Dollars are called greenbacks because that is the color of the back side of the paper money.
The color black is used often in expressions. People describe a day in which everything goes wrong as a black day. The date of a major tragedy is remembered as a black day. A blacklist is illegal now. But at one time，some businesses refused to employ people who were on a blacklist for belonging to unpopular organizations. If you had your wallet stolen while doing some shopping, you may call it ______ .
| A．a white day | B．a black day |
| C．a red day | D．a green day |
Suppose a Mr. Brown says he is very happy because his three children* are all in the pink, this means all his children are ______ .
| A．lucky and wealthy |
| B．gentle and modest |
| C．fit and healthy |
| D．creative and energetic |
When she got home and found nothing had been done by her husband, Jane was really ______ .
| A．red hot | B．green |
| C．blue | D．black |
In the following paragraph, the writer might tell the readers something about ______ .
| A．unpopular polarizations in the world |
| B．people's response towards a black day |
| C．the influence of the traditional blues |
| D．more words about colors，such as brown |
For many in the United States, Arab-Americans are an invisible part of the population. Though Arab-Americans as a community have made great contributions to American society in fields from literature to politics to medicine, many Americans know very little about Americans of Arab backgrounds.
Arab history in the United States goes back to the late 1800's when large numbers of Arab immigrants first began making their journey to a land known simply as "Amreeka".
Historians generally describe Arab immigration to America in two waves. The first wave took place between 1860 and 1924. The first wave consisted of Lebanese and Syrian，and some Egyptian immigrants. These new immigrants，who were mostly Christians, came to America in search of better opportunities. Even the doomed Titanic , which set sail for America in 1912, had close to a hundred Arab passengers aboard. The majority of Arab-Americans today are descendents of the first wave of immigrants； they are the third or more generation Americans.
The second wave of immigrants followed after World War Ⅱ， caused by political unrest in the Middle East. This second wave of immigrants consists of mainly Arab Muslims (穆斯林)and continues to this day.
Arab-Americans make up 3 million of the population in the United States，according to demographers. And quite different from popular belief, 64 percent of them are American-born. Eighty-two percent of Arab-Americans are US citizens.
Arab-Americans are beyond the national average in both education and income. Education is important among Arab-Americans； 82 percent have high school diplomas, 36 percent have bachelor's degrees or higher, and 15 percent have graduate degrees. The- median (中位数的)average income among Arab-Americans is $39, 580, which is higher than the US average. What would be the best title for the text?
| A．Arabs in America. |
| B．The Two Arab Immigration Waves to America. |
| C．Arab-Americans, Contributions to America. |
| D．Arab-Americans, Education and Income. |
The first wave of immigrants took place because ______ .
| A．all Arabs were Christian at that time |
| B．Arabs wanted to hunt for a better development |
| C．the Second World War broke out |
| D．Arabs wanted to gain higher income |
The writer of this passage mentioned Titanic ______ .
| A．to tell us that taking ship at that time was dangerous |
| B．because Titanic became a well-known disaster |
| C．to show us there were many Arabs flocking into America at that time |
| D．to inform us that Arabs are brave enough |
From the last paragraph we can infer that ______ .
| A．Arab-Americans are much more clever than native Americans |
| B．Arab-Americans are hard-working people |
| C．the higher education you receive, the higher income you will get in America |
| D．Arab-Americans play the most important role in the American average in both education and income |
The Poetry Foundation recently named American poet Jack Prelutsky as the nation's first children's poet laureate (桂冠诗人). The group created the award as a way to increase children’s love of poetry.
As children's poet laureate, Jack Prelutsky will give two public readings in the next two years. He will also advise the Poetry Foundation about children's literature and take part in projects concerning children and poetry.
Jack Prelutsky has been writing poetry for children for almost forty years. He has written more than thirty-five books of poems. His first book was called /4 Gopher in the Garden. It was published in 1967. His latest is called Behold the Bold Umbrellaphant and Other Poems.
Prelutsky is well known for creating new words by combining two words to creat a new kind of creature. For example, he combined "radish" with "shark" to get "radishark", "Lion" and "broccoli" became "broccolion", He also created "umbrellaphant", a mixture of the words "umbrella" and "elephant".
Jack Prelutsky says that children like his poems because he writes about things they care about. Poetry researchers say that Jack Prelutsky's poems recognize children's feeling. An example of this is the poem My Sister Is a Werewolf which is about how it feels to be different.
Jack Prelutsky also writes poems about American holidays. His poem It's Halloween is a very famous one about the holiday celebrated at the end of October. Which of the following can be the best title of the passage?
| A．Poems with New Words Grow Popular |
| B．First Children's Poet Laureate Named |
| C．Children's Love for Poetry Increased |
| D．Jack Prelutsky Awarded Nationwide |
What is Jack Prelutsky famous for?
| A．Creating new words in his poems. |
| B．His productivity. |
| C．His long time of writing. |
| D．His poems about American holidays. |
Children are in favour of his poems because ______ .
| A．they are easy to understand |
| B．the poet is famous |
| C．children like reading new words |
| D．the poet understands their feelings |
Put the following items in right order according to the passage.
a. two public readings
b. A Gopher in the Garden
c. Behold the Bold Unbrellaphant and Other Poems
d. My Sister Is a Werewolf
| A．b-c-d-a | B．d-a-c-b |
| C．b-d-c-a | D．a-b-c-d |
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