Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday.
Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights.
“Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal.
They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space.
The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added.
Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream.
The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth. French scientists did their research on Russian astronauts, because _______.
| A．they only cared for the Russian astronauts |
| B．they were not interested in their own astronauts |
| C．the Russian government invited them to do their research |
| D．the Russian astronauts worked in space for a long time |
Scientists have found that _______.
| A．the BMD loss may cause serious illness to astronauts |
| B．the BMD loss may cause some change in astronauts’ bodies |
| C．astronauts shouldn’t care about the BMD loss |
| D．astronauts should take some calcium before space travel |
What cause the BMD loss to astronauts, according to this passage?
| A．The food they eat in space. | B．The drinks they take in space. |
| C．The temperature in space. | D．The gravity in space. |
In the third paragraph, the word “striking” means ______.
| A．unusual | B．simple | C．weak | D．slow |
Have you ever wondered?
1.Why do airplanes take longer to fly west than east?
It can take five hours to go west-east from New York(NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon know as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes movement a constams air speed thus go faster in the west-east direction when the air moving with the wind than in the opposite direction.
2 What would happen if the gravity on Earth was suddenly turned off?
Supposing we could magically turn off gravity. Would buildings and other structures float away? What happened would depend on how strongly the things were attached to the Earth. The Earth is moving at quite a speed moving at over a thousand miles per hour. If you turn something round your head on a string, it goes around in a circle until you let go of the strong go of the string. Things not attacked to the Earth would fly off in a straight line . People in buildings would suddenly shoot upwards at a great speed until they hit the ceiling. Most things would fly off into space.
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What information coa we get from the first passage?
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The word"shoot"underlined in the 2nd passage probably means"".
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It can be interred that without gravity.
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Where can wemost probably read this text?
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American cities are similar to other cities around the world:In every country, cities reflect the values of the culture.American cities are changing, just as American society is changing.
After World War ?, the population of most large American cities decreased; however, the population in many Sun Belt cities increased.Los Angeles and Houston are cities where population shifts(转移)to and from the city reflects the changing values of American society.In the late 1940s and early 1950s,city residents(居民)became wealthier.They had more children so they needed more space.They moved out of their apartments in the city to buy their own homes.They bought houses in the suburbs(郊区)．
Now things are changing.The children of the people who left the cities in the 1950s are now adults.Many, unlike their parents, want to live in the cities.They continue to move to Sun Belt cities and older ones of the Northeast and Midwest.Many young professionals are movi
ng back into the city.They prefer the city to the suburbs because their jobs are there; or they just enjoy the excitement and possibilities that the city offers.
This population shift
is bringing problems as well as benefits.Countless poor people must leave their apartments in the city because the owners want to sell the buildings or mak
e apartments for sale instead of for rent.In the 1950s, many poor people did not have enough money to move to the suburbs; now many of these same people do not have enough money to stay in the cities.
Only a few years ago, people thought that the older American cities were dying.Some city residents now see a bright, new future.Others see only problems and conflicts.One thing is sure:many dying cities are alive again.
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What does the author think of cities all over the world?
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| 2． |
Why did American city residents want to live in the suburbs after World War Ⅱ?
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| 3． |
According to the 4th paragraph, a great many poor people in American cities.
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We ear comude from the text that.
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阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。
The engineer Camillo Olivetti was 40 years old when he started the company in 1908. At his factory in lvera, he designed and produced the first Italian typewriter. Today the company's head office is still in Ivrea, near Turin, but the company is much lareer than it was in those days and there are offices all around the world.
By 1930 there was a staff of 700 and the company turned out 13,000 machines a year. Some went to customers in Italy, but Olivetti exported more typewriters to other countries.
Camilllo's son, Adriano, started working for the company in 1924 and later he became the boss. He introduecd a standard speed for the production line and he employed technology and desion specialists. The company developed new and better typewriters and the calculators（计算器）.In 1959 it prodyced the ELLA computer system. This was the first mainframe（主机）computer designed and brade in Italy.
After Adriano died in 1960, the company had a period of financial problems. Other companies, especially the Janpanese, made faster progress in electronic technology than the Italian company.
In 1978, Carlo de Benedetti became the new boss. Olivetti increased its marking and service networks and made agreements with other companies to design and produce more advanced office equipment. Soon it became one, of the world's leading companies in informationg technology and communications. There are now five independent companies in the Olivetti group --- one for personal computers,one for other office equipment, one for systerms and servicse, and two for telecommunications.
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From the text we learn that.
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What was probably the direct result of Olivetti,s falling behind in electronic technology?
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What do we know about Olivetti ?
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The best title for the text would be.
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To err is human. To blame the other guy is even more human.
Common sense is not all that common.
Why tell the truth when you can come up with a good excuse?
These three popular misquotes(戏谑的引语)are meant to be jokes, and yet they tell us a lot about h
uman nature .To err, or to make mistakes, is indeed a part of being human, but it seems that most people don’t want to accept the responsibility for the problem. Perhaps it is the natural thing to do .The original quote about human nature went like this:” To err is human, to forgive, divine(神圣的).”This saying mirrors an deal people should be forgiving of others’ mistakes. Instead, we tend to do the opposite –find someone else to pass the blame on to. However, taking responsibility for something that went wrong is a making of great maturity.
Common sense is what we call clear thought. Having common sense means having a good general plan that will make things work well, and it also means staying with the plan. Commonsense tells you 
that you take an umbrella out into a rainstorm, but you leave the umbrella home when you hear a weather forecast for sunshine．Common sense does not seem to be common for large organizations, because there are so many things going on that one person cannot be in charge of everything. People say that in a large company,”the right hand does not know what the left hand is doing.”
And what is wrong with a society that thinks that making up a good excuse is like creating a work of art? One of the common problems with making excuses is that people, especially young people. get the idea that it’s okay not to be totally honest all the time. There is a corollary(直接推论)to that: if good excuse is “good”even if it isn’t honest, then where is the place of the truth?
1. According to tile passage, which of following seems the most human?
A. To search for truth． B. To achieve one’s ideal
C. To make fun of others’mistakes． D. To criticize others for one’s own error.
2．According to the author, what is a sign of a man’s maturity?
A．Doing things his own way.
B．Bearing responsibility for his mistakes.
C．Making as few mistakes as possible．
D．Thinking seriously about his wrongdoing.
3．Which of the following is N0T based on common sense?
A．A man tries to take charge of everything in a large company.
B．A student
goes out with an umbrella in stormy weather.
C．A company’s next move follows a good plan．
D．A lawyer acts on fine judgments．
4. What is the author’s opinion about a good excuse?
A. Making a good excuse is sometimes a better policy.
B. Inventing a good excuse needs creative ideas.
C. A good excuse is as rewarding as honesty.
D. Bitter truth is better than a good excuse.
5. What would be the best title for his passage?
A. A Mirror of Human Nature B. To Blame or to Forgive
C. A Mark of Maturity D. Truth or Excuse
In the kitchen of my mother’s houses there has always been a wooden stand（木架）with a small notepad（记事本）and a hole for a pencil.
I’m looking for paper on which to note down the name of a book I am recommending to my mother. Over forty years since my earliest memories of the kitchen pad and pencil, five houses later, the current paper and pencil look the same as they always did. Surely it can’t be the same pencil? The pad is more modern, but the wooden stand is definitely the original one.
“I’m just amazed you still have the same stand for holding the pad and pencil after all these year.” I say to her, walking bank into the living-room with a sheet of paper and the pencil. “You still use a pencil. Can’t you afford a pen?”
My mother replies a little sharply. “It works perfectly well. I’ve always kept the stand in the kitchen. I never knew when I might want to note down an idea, and I was always in the kitchen in these days.”
Immediately I can picture her, hair wild, blue housecoat covered in flour, a wooden spoon in one hand, the pencil in the other, her mouth moving silently. My mother smiles and says, “One day I was cooking and watching baby Pauline, and I had a brilliant thought, but the stand was empty. One of the children must have taken the paper. So I just picked up the breadboard and wrote it all down on the back. It turned out to be a real breakthrough for solving the mathematical problem I was working on.”
This story—which happened before I was born—reminds me how extraordinary my mother was, and is, as a gifted mathematician. I feel embarrassed that I complain about not having enough child-free time to work. Later, when my mother is in the bathroom, I go into her kitchen and turn over the breadboards. Sure enough, on the back of the smallest one, are some penciled marks I recognize as mathematics. Those symbols have traveled unaffected through fifty years, rooted in the soil of a cheap wooden breadboard, invisible（看不到的）exhibits at every meal.
1．Why has the author’s mother always kept the notepad and pencil in the kitchen?
A．To leave messages. B．To list her everyday tasks.
C．To note down maths problems. D．To write down a flash of inspiration.
2. What is the author’s original opinion about the wooden stand?
A. It has great value for the family.
B. It needs to be replaced by a better one.
C. It brings her back to her lonely childhood.
D .It should be passed on to the next generation.
3. The author feels embarrassed for_______.
A. blaming her mother wrongly.
B. giving her mother a lot of trouble.
C. not making good use of time as her mother did.
D. not making any breakthrough in her field.
4. What can be inferred from the last paragraph?
A .The mother is successful in her career.
B. The family members like traveling.
C. The author had little time to play when young.
D. The marks on the breadboard have disappeared.
5. In the author’s mind ,her mother is_________.
A. strange in behavior. B. keen on her research.
C. fond of collecting old things. D. careless about her appearance.