American researchers have developed a technique that may become an important too
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American researchers have developed a technique that may become an important tool in fighting AIDS virus from attacking its target-cells in the body"s defense system．When AIDS virus enters the blood，it searches for blood cells called T4 lymphocytes(淋巴细胞)．The virus connects to the outside of T4 lymphocytes．Then it forces its way inside．There it directs the cells" genetic material to produce copies of the AIDS virus．This is how AIDS spreads．
Researchers think they may be able to stop AIDS from connecting to T4 ceils．When AIDS virus finds a T4 cell，it actually connects to a part of the cell called CD4 protein．
Researchers want to fool the virus by putting copies or clones of the CD4 protein into the blood．This way the AIDS virus will connect to cloned protein instead of the real ones．Scientists use genetic engineering methods to make the clones．Normally a CD4 protein remains on the T4 cell at all times；the AIDS virus must go to it．
In a new technique，however，the cloned CD4 protein is not connected to a cell．It floats freely，so a lot more can be put into the blood to keep the AIDS virus away from real CD4 protein on T4 cells．One report says the．AIDS virus connects to cloned protein just as effectively as it connects to real protein．That report was based on tests with blood cells grown in labs．The technique is just now beginning to be tested in animals．If successful，it may be tested in humans within a year．
小题1:The new technique can .| A．cure AIDS | | B．kill the AIDS virus | | C．prevent the AIDS virus from spreading | | D．produce new anti-AIDS cells |
小题2:When the AIDS virus enters the blood，it is reproduced by .| A．itself | | B．the blood cells | | C．the CD4 protein | | D．the genetic material of T4 lymphocytes |
小题3:The AIDS virus connects to cloned protein instead of the real CD4 protein because .| A．cloned protein stays On the T4 cells | | B．it connects to cloned protein more effectively | | C．cloned protein is made by genetic engineering methods | | D．cloned protein floats freely，and many more can be put into the blood |
小题4:Which of the following statements is NOT true?| A．The new technique has been tested in labs． | | B．The new technique is being tested in animals． | | C．The new technique may be tested in humans． | | D．The new technique is now under clinic test． |
小题5:The best title for this passage is ．| A．AIDS-a deadly disease | | B．A new technique in fighting AIDS | | C．The spread of AIDS virus | | D．The cloned CD4 protein |
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答案
小题1:C
小题2:D
小题3:D
小题4:D
小题5:B |
解析
文章介绍了一种新的治疗AIDS病的疗法。
小题1:推理题。根据第二段When AIDS virus finds a T4 cell，it actually connects to a part of the cell called CD4 protein．可知这样做是别人AIDS病毒接触到真正的T4 lymphocytes，实际上是阻止AIDS的传播。
小题2:细节题。根据第一段的第四行There it directs the cells" genetic material to produce copies of the AIDS virus．
小题3:细节题。根据最后一段第2,3行It floats freely，so a lot more can be put into the blood to keep the AIDS virus away from real CD4 protein on T4 cells．
小题4:细节题。根据最后一段最后两行That report was based on tests with blood cells grown in labs．The technique is just now beginning to be tested in animals。
小题5:主旨大意题。通读全文尤其是主题段第一段可知文章介绍了一种新的治疗AIDS病的疗法。 |
举一反三
"We do look very different; we"re older. Leo"s 38, I"m 37. We were 21 and 22 when we made that film. You know, he"s fatter now -- I"m thinner.". So says Kate Winslet, who is thrilled at the 3-D re-release of Titanic to coincide with the 100th anniversary of the ship"s demise. “ It happens every time I get on any boat of any kind." She recalls. There are all the people who want her to walk to the front of the ship and re-create her famous pose, arms flung wide. Most people remember the tragedy: The British passenger ship -- said to be unsinkable -- hit an iceberg and sank on April 15, 1912, during its maiden voyage from England to New York City. More than 1,500 people died. But little known is what the world learned from the sinking to prevent future incidents.
Probably the greatest deficiency （不足）of the Titanic was that she was built 40 years before the widespread use of the wonderful invention radar(雷达). Her only defense against icebergs and hidden obstacles was to rely on manned lookouts. On that fateful night the eyesight of trained lookouts only provided 37 seconds of warning before the collision.
Traveling at nearly 30 miles an hour the Titanic was moving far too fast to avoid the huge iceberg. The warning did prevent a head-on collision as the officer on the bridge managed to turn the ship slightly.
The last ship to send a warning was the California. She was within ten miles of the Titanic during the disaster, but her radio operator went to bed at midnight and never received any of the SOS messages from the Titanic. That was one of the important lessons learned from the catastrophe, the need for 24-hour radio operators on all passenger liners.
Another lesson learned was the need for more lifeboats. The Titanic remained afloat(漂浮) for almost three hours and most of the passengers could have been saved with enough lifeboats.
1,500 passengers and workers died in the 28 degree waters of the Atlantic. Out of the tragedy, the sinking did produce some important maritime reforms. The winter travel routes were changed to the south and the Coast Guard began to keep an eye on the location of all icebergs. The new rules for lifeboats were obvious to all. There must be enough lifeboats for everybody on board.
The most important lesson learned was that no one would ever again consider a ship unsinkable- no matter how large or how well constructed. Never again would sailors place their faith in a ship above the power of the sea.
小题1:The text mainly tells us ______.| A．the reason why the Titanic sank in the Atlantic Ocean | | B．how the unsinkable ship of Titanic sank in the Atlantic Ocean | | C．the lessons that we could learn from the accident of theTitanic | | D．the things we should do to protect the lives on the ship |
小题2:According to the passage, which of the following could we infer?| A．If the captain had been more careful, he could have had the chance to save the Titanic. | | B．If radar had existed 40 years ago, the Titanic would have never disappeared from the world. | | C．If the lookout had had much more experience, he could have had the time to save the Titanic. | | D．If there had been enough lifeboats on the Titanic, the Titanic would not have sunk in the Atlantic. |
小题3:What would be the best title for the passage?| A．Lessons from the Titanic | B．Technology is Important | | C．Demands of Passengers | D．Power of Sea |
小题4:What’s the sailors’ attitude towards the ships after the tragedy?| A．They think there really exists the unsinkable ship. | | B．They think ships could eventually defeat the sea. | | C．They think there is no power that could control the sea. | | D．They think the bigger the ship is, the safer it is. |
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Work Your Mind
Here’s something to think about the next time you ask your teacher for help: struggling with schoolwork on your own can help you learn. According to a recent study, the more you struggle while you are learning new information, the better you can remember it later.
This theory might surprise you. When teachers are presenting new information, they often give students lots of help. But a new study shows this may not be the best way to support learning. “Don"t be too quick to get help when learning something new,” education expert Manu Kapur told TFK. “Try to work on it yourself even if it means trying different ways.”
Kapur came up with the idea that struggling can lead to better learning. Then he tested it out on students in Singapore. He separated students into two groups. In the first group, students were asked to solve math problems with the teacher’s help. In the second group, students were asked to solve the same problems by helping one another, instead of getting help from the teacher.
With the teacher’s help, students in the first group were able to find the correct answers. Students in the second group did not solve the problems correctly. But they did come up with a lot of good ideas. The students were then tested on what they had learned. The group without any help from a teacher scored much higher than the group who had help. Kapur said working to find the answers helped students understand the process, not just the solution.
Kapur’s advice for kids is to put a lot of effort into learning something new rather than going to your teacher for help. “Simply doing a little work or nothing at all won’t work,” says Kapur. “The struggle needs to be a genuine attempt to figure out or solve a problem in as many ways as possible.”
小题1:When you have doubt on schoolwork, you’d better ____________. | A．ask your teacher for help | | B．make it clear by yourself | | C．ask your classmates to help you | | D．ask your parents for help |
小题2:What’s Manu Kapur educational idea on learning new knowledge? | A．Give students much help as soon as possible. | | B．Let students learn it on themselves in one way. | | C．Let students learn it by themselves in the same way. | | D．Let students learn it for themselves in different ways. |
小题3:How did Kapur check his idea on better learning? | A．By asking questions. | | B．By solving art problems. | | C．By group comparations. | | D．By solving science problems. |
小题4:What is most important in learning knowledge?| A．Getting the teacher’s help. | | B．Getting the student’s help. | | C．Grasping the learning course. | | D．Receiving the final solution. |
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Baby girls make their way directly for dolls as soon as they can crawl, while boys will head for cars, a study has shown. The findings, the first to show differences in very young babies, suggest there is a biological basis to their preferences.
Psychologists Dr Brenda Todd from City University London carried out an experiment involving 90 babies aged 9 months to 36 months. The babies were allowed to choose from seven toys. Some were typically boys’ toys ---- a car, a digger, a ball and a blue teddy. The rest were girls’ toys: a pink teddy, a doll and a cooking set. They were placed a meter away from the toys；and could pick whichever toy they liked their choice and the amount of time they spent playing with each toy were recorded.
Of the youngest children (9 to 14 months), girls spent significantly longer playing with the doll than boys, and boys spent much more time with the car and ball than the girls did. Among the two and three-year-olds, girls spent 50 percent of the time playing with the doll while only two boys briefly touched it. The boys spent almost 90 percent of their time playing with cars, which the girls barely touched. There was no link between the parents’ view on which toys were more appropriate for boys or girls, and the children’s choice.
Dr Brenda Todd said, “Children of this age are already exposed to much socialization. Boys may be given ‘toys that go’ while girls get toys they can care for, which may help shape their preference. But these findings agree with the former idea that children show natural interests in particular kinds of toys. There could be a biological basis for their choices. Males through evolution have been adapted to prefer: moving objects, probably through hunting instincts（本能）, while girls prefer warmer colors such as pink, the colour of a newborn baby.”
小题1:Baby boys and girls have different toy preferences probably because ________. | A．baby boys are much more active | | B．baby girls like bright colours more | | C．their parents treat them differently | | D．there is a natural difference between them |
小题2:Both baby boys and baby girls like to play with ________ according to the study.| A．a ball | B．a teddy | C．a car | D．a doll |
小题3:What can we infer from Paragraph 3?| A．Nine-month-old baby boys don’t play with dolls at all. | | B．Two-year-old baby girls sometimes play with cars and balls. | | C．The older the babies are, the more obvious their preference is. | | D．Parents should teach their babies to share each other’s toys. |
小题4:What conclusion did Dr. Brenda Todd draw from the results of the study?| A．Adults purposely influence their babies’ preference. | | B．Babies’ preference isn’t affected by social surroundings. | | C．Baby boys preferring to moving toys will be good at hunting. | | D．Baby girls preferring warmer colors will be warm-hearted. |
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As computers become more popular in China, Chinese people are increasingly relying on computer keyboards to input Chinese characters. But if they use the computer too much, they may end up forgetting the exact strokes（笔画）of each Chinese character when writing on paper. Experts suggest people, especially students, write by hand more.
Do you write by hand more or type more? In Beijing, students start using a computer as early as primary school. And computer dependence is more wide-spread among university students. Almost all their assignments and essays are typed on a computer.
All the students interviewed say they usually use a computer.
It"s faster and easier to correct if using a computer. And that"s why computers are being applied more and more often to modern education. But when people are taking stock in computers increasingly, problems appear.
“When I"m writing with a pen, I find I often can"t remember how to write a character, though I feel I’m familiar with it.”
“I"m not in the mood to write when faced with a pen and paper.”
Many students don"t feel this is something to worry about. Now that it"s more convenient and efficient to write on a computer, why bother to handwrite?
Many educators think differently. Shi Liwei, the headmaster of a famous primary school in the capital said, “Chinese characters enjoy both practical and aesthetic (审美的) value. But those characters typed with computer keyboards only maintain their practical value. All the artistic beauty of the characters is lost. And handwriting contains the writer"s emotion. Through one"s handwriting, people can get to know one"s thinking and personality. Beautiful writing will give people a better first impression of them.”
To encourage students to handwrite more, many primary schools in Beijing have made writing classes compulsory (必修的) and in universities, some professors are asking students to turn in their homework and essays written by hand.
小题1:Which of the following can best serve as the title of the passage?| A．The Importance of Handwriting and Typing | | B．To Type or To Hand Write | | C．Writing By Computer Will Replace Writing By Hand | | D．Practical and Aesthetic Value of Chinese Characters |
小题2:The students interviewed prefer to write using a computer mainly because ______.| A．they are usually asked to e-mail their Homework and Essays | | B．they can correct the mistakes they make quickly and conveniently | | C．they find it not easy to remember how to write a character | | D．computers have become a trend and fashion in China |
小题3:Which of the following statements is NOT TRUE of the advantages of handwriting?| A．Handwriting contains the writer"s emotion. | | B．The writer’s thinking and personality are shown in his or her handwriting. | | C．Handwriting can impress people well and build one’s self-confidence. | | D．Chinese characters enjoy both practical and aesthetic value. |
小题4:The underlined expression “taking stock in” (Paragraph 4) probably means _____.| A．getting bored with | B．getting dependent on | | C．becoming crazy about | D．getting curious about |
小题5:We can draw the conclusion from the passage that _______.| A．more and more students will give up writing on a computer | | B．writing by hand will give way to typing by computer one day | | C．more and more students will pay attention to handwriting | | D．the typing article better expresses one’s emotion and quality |
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It is always hard for a small fish to live in a big pond. Pluto"s recent departure from the classical planet family clearly proves that size really matters.
Astronomers voted on August 24 to create the first scientific definition of the word planet, and Pluto obviously didn"t make the cut. It turned out to be only a "dwarf planet" (矮行星). After weeks of heated debate, over 2,500 astronomers from 73 countries voted on the definition of a "planet" at a conference of the international Astronomical Union (IAU). According to the definition, a planet must have a clear neighborhood around its orbit. Pluto has widely been considered a planet since its discovery in 1930. Unfortunately, it has a special orbit which overlaps with Neptune"s. It is all because, compared with Neptune, Pluto is very small. It is attracted by Neptune"s gravity when the two planets get closer.
According to IAU, a "dwarf planet" should have an orbit around the Sun. It will not have a clear neighborhood around its orbit, and must not be a satellite. The new classification means that the science textbooks will have to be updated. The solar system is now made up of the eight "classical planets," together with a number of dwarf planets. The classical planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The debate over Pluto"s status started in 1992. After an advanced telescope was sent into space, astronomers started find a belt of objects, which lies beyond Neptune. The belt contains nearly 1,000 objects, including Pluto. As they continued the exploration, scientists recently discovered at least 41 dwarf planets at the edges of the solar system. There are at least two objects of a similar size to Pluto.
It seems that even if the IAU had kept Pluto"s status as a planet, the classical theory of nine planets in the solar system would have had to be changed, but the other way around. More dwarf, planets of a similar size to Pluto would join the family of planets. Scientists will probably find many more dwarf planets.
小题1:According to the passage, Pluto is .| A．a planet which has a clear neighborhood around its orbit | | B．a satellite of Neptune which was discovered in 1930 | | C．the smallest planet in the solar system | | D．a planet which has an orbit around the sun |
小题2:The sentence "It is always hard for a small fish to live in a big pond" quoted in the beginning of the passage is used to .| A．tell us a small fish can hardly survive in the big pond | | B．tell us the size of an object really matters | | C．mean that a small planet can hardly exist in the solar system | | D．explain the disappearanee of Pluto in the solar system |
小题3:From the last paragraph we can infer that if IAU kept Pluto"s status as a planet, the number of planets in the solar system would be .| A．eight | B．nine | C．less than nine | D．more than nine |
小题4:Which of the following statements is NOT true aceording to the passage?| A．According to definition of a "planet", if Pluto were bigger it would not have left the classic planet family. | | B．It"s quite possible for dwarfs to lose if they compete with big men | | C．Pluto has a special orbit which overlap with Neptune"s, because it is so small as to be attraeted by Neptune"s gravity when the two planets get closer | | D．A "dwarf planet", which can not be a satellite without a clear neighborhood around its orbit, should have an orbit around the Sun. |
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