At first sight the planet Mars(火星)does not appear very welcoming to any kind of
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At first sight the planet Mars(火星)does not appear very welcoming to any kind of life. It has very little oxygen and water, the temperature at night is below 50 degrees and winds of 100 miles(161 kilometers)per hour cause severe dust storms. However, the surface of the planet seems to show that water flowed across it at some time in the past, and it is believed that there would be enough ice at the poles to cover the planet with water if it melted. Although there is no life on the Mars now, some scientists think there may have been some form of life a long time ago. At that time, the planet had active volcanoes(火山); the atmosphere was thicker and warmer; and there was water. In fact, in some ways the Mars may have been similar to the Earth, where life exists.
Some people believe that the Mars could support life in the future if the right conditions were produced. The first step would be to warm the planet using certain gases which trap the Sun’s heat in the planet’s atmosphere. With warmth, water and carbon dioxide, simple plants could begin to grow. These plants could slowly make the Mars fit to live on. It is judged that the whole process might take between
100, 000 and 200, 000 years. In the meantime, people could begin to live on the planet in a special closed environment. They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.
小题1: According to the passage, the planet Mars has no on it. | A．winds | B．dust | | C．mountains | D．animals |
小题2:It is believed that on the Mars now . | A．there is a large amount of ice at the poles | | B．there is a thicker and warmer atmosphere | | C．there are some kinds of simple plants | | D．there are many active volcanoes |
小题3: What is the topic of Paragraph 2? | A．Certain gases should be used to warm the Mars. | | B．Plants should be grown to make the Mars fit to live on. | | C．The Mars could support life on right conditions in the future. | | D．People could live on the Mars in a special closed environment. |
小题4: The most suitable title for the passage is . | A．No Life on the Mars | | B．Study of the Mars | | C．The Possibility of Life on the Mars | | D．Future Conditions on the Mars |
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答案
小题1:D
小题2:A
小题3:C
小题4:C |
解析
【文章大意】本文主要分析了火星上的现状以及对过去火星历史的推测, 从而展望了未来火星适合人类生存的可能性。
小题1:选D。细节理解题。在第一段中的细节中提到了winds, dust storms, volcanoes, 但是没有涉及第四项, 根据there is no life on the Mars now知火星上没有动物生存, 故选D项。
小题2:选A。细节理解题。根据第一段中的it is believed that there would be enough ice at the poles to cover the planet with water if it melted. 可知火星的两极有大量的冰, 融化后就会有水, 故A项正确。
小题3:选C。主旨大意题。根据第二段的叙述可知主要讲未来在火星上如何创造适合人类生存的条件, 也就是说第一句话为本段的主题句, 故本段主题为C项。
小题4:选C。主旨大意题。本文主要分析了火星上的现状以及对过去火星历史的推测, 从而展望了未来火星适合人类生存的可能性, 故C项作为题目合适。 |
举一反三
If you want to help children develop language and speech skills, UCLA researchers say, listening to what they have to say is just as important as talking to them.
The effect of a conversation between a child and an adult is about six times as great as the effect of adult speech input(输入)alone, the researchers found. “Adults speaking to children helps language develop, but what matters much more is the interaction, ”said the study’s lead author, Frederick Zimmerman, an associate professor in the School of Public Health at the University of California, Los Angeles. The researchers also found that TV viewing didn’t have much of an effect—positively or negatively—as long as it wasn’t displacing conversations between an adult and a child.
The UCLA study included 275 families with children between 2 months and 48 months old. They represented a variety of incomes and education. The researchers found that, in an average day, children heard about 13, 000 spoken words from adults and participated in about 400 adult-child conversations a day.
Assessed separately, factors positively associated with language development included each additional 100 conversations a day and each 1, 000 words increase in the number of words spoken by adults and heard by children. When looked at alone, TV was negatively associated with language development. But, when these three factors were analyzed together, the only one that stood out was conversation between adults and children.
“The more a child speaks and interacts with an adult, the better idea a parent has about where the child is”, Zimmerman said. “Although it’s mostly done unconsciously, parents will provide feedback and correct mistakes. They’ll also tailor their speech to the child. Parents can give the children words by talking to them about what they’re doing, such as, ‘I’m putting on your pajamas now’. But give your child the opportunity to talk, hopefully without the rest of the noise in the environment, ”she added. “If parents can carve out some conversation time—maybe at bath time or at dinner time—that’s a wonderful thing. ”
小题1: The researchers also found that TV viewing . | A．could have a positive effect on a child’s language development | | B．had a little effect on a child’s language development | | C．affected a child’s language development more negatively than positively | | D．affected a child’s language development both negatively and positively |
小题2:Frederick Zimmerman would probably agree that . | A．parents should let their children talk most of the time | | B．children should watch TV programs selectively | | C．the conversation between parents and children should be two-way | | D．it’s no good for parents to correct their children’s mistakes when they are speaking |
小题3: We can conclude from the last paragraph that . | A．parents should let a child repeat what he or she says | | B．bath time or dinner time is the best chance for parents to talk to a child | | C．parent-child conversation can be carried out at any proper time | | D．parents should leave a child talking alone |
小题4: What would be the best title for the passage? | A．Talk with kids, not at them | | B．Let your children voice their own opinions | | C．How to develop a child’s language ability | | D．The importance of early child language development |
小题5:The underlined word “tailor” in the last paragraph can be best replaced by . | A．control | B．improve | | C．pass | D．adjust |
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Bananas are one of the world’s most important food crops. They are also one of the most valuable exports. Bananas do not grow from seeds. Instead, they grow from existing plants. Bananas are threatened by disease because all the plants on a farm are copies of each other. They all share the same genetic weaknesses. For example, the Cavendish banana is most popular in North American and European markets. However, some kinds of fungus organisms easily infect the Cavendish. Black Sigatoka disease affects the leaves of Cavendish banana plants. The disease is controlled on large farms by putting chemicals on the plants’ leaves. Farmers put anti-fungal chemicals on their crops up to once a week.
Another fungal disease is more serious. Panama disease attacks the roots of the banana plants. There is no chemical treatment for this disease. Infected plants must be destroyed. Panama disease has affected crops in Southeast Asia, Australia and South Africa. There is concern that it may spread to bananas grown in the Americas. This could threaten an important export product for Central and South America.
The International Network for the Improvement of Banana and Plantain supports research on bananas. The group has headquarters in France and other offices in the major banana-growing areas of the world. The group says that more research must be done to develop improved kinds of bananas. The group says that fungal diseases mainly affect only one kind of banana. In fact, there are five hundred different kinds of bananas. Food and Agriculture Organization of the United Nations has said that the Cavendish banana represents only 10% of world production.
The U. N. agency says farmers should grow different kinds of bananas. This protects against diseases that affect only one kind. Experts warn that disease may cause the Cavendish banana to disappear. This happened earlier to another popular banana because of its genetic weakness against disease.
小题1:What does this passage mainly tell us? | A．Bananas are the world’s most important food crops. | | B．The risk to a popular banana shows need to grow other kinds. | | C．There are five hundred different kinds of bananas. | | D．How to grow bananas in different countries. |
小题2:Bananas are threatened by disease because . | A．they grow from seeds | | B．they are one of the most valuable exports | | C．the only way to prevent it is to put chemicals on their leaves | | D．they have genetic weaknesses against disease |
小题3: Panama disease . | A．doesn’t belong to fungal disease | | B．affects the leaves of banana plants | | C．destroys bananas more seriously than Black Sigatoka disease | | D．has spread to bananas all over the world |
小题4: We can infer from Paragraph 3 that . | A．the center of the group is in the US | | B．the Cavendish banana covers only a small part of the yield of bananas | | C．the key to solving the disease is to research all kinds of bananas | | D．each fungal disease affects five hundred different kinds of bananas |
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Ten years ago, with only about 1, 000 pandas left in the world, China was desperately trying to clone(克隆)the animal and save the endangered species(物种). That was a move similar to what Texas A & M University researchers had been undertaking for the past five years in a project called “Noah’s Ark”(诺亚方舟).
Noah’s Ark was aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine, said there would be enough of the basic building blocks to reintroduce the species in the future.
It was estimated that as many as 2, 000 species of mammals, birds reptiles would become extinct in over 100 years. The panda, native only to China, was in danger of becoming extinct in the next 25 years.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They were then trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
“The nucleus transfer(核子移植)of one species to another is not easy, and the lack of available(capable of being used)panda eggs could be a major problem,”Kraemer believed. “They will probably have to do several hundred transfers to result in one pregnancy(having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort, ”added Kraemer, who was one of the leaders of the project at Texas A& M, the first-ever attempt at cloning a dog.
“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed. ”
At present, the project has worked. The number of the pandas has increased to more than 1, 500.
小题1:The aim of “Noah’s Ark” project was to . | A．make efforts to clone the endangered pandas | | B．save endangered animals from dying out | | C．collect DNA of endangered animals to study | | D．transfer the nucleus of one animal to another |
小题2: According to Professor Kraemer, the major problem in cloning pandas would be the lack of . | A．available panda eggs | B．host animals | | C．qualified researchers | D．enough money |
小题3: The best title for the passage may be . | A．China’s Success in Pandas Cloning | | B．The First Cloned Panda in the World | | C．Exploring the Possibility to Clone Pandas | | D．China—the Native Place of Pandas Forever |
小题4:From the passage we know that . | A．Kraemer and his team had succeeded in cloning a dog | | B．scientists tried to implant a panda’s egg into a rabbit | | C．Kraemer would work with Chinese scientists in clone researches | | D．about two thousand species would probably die out in a century |
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It was July 1976. An unmanned spaceship, Viking One, had arrived at Mars. On July 20th, the spaceship . Part of it continued toward a landing on the planet. It fell through the late afternoon Mars’ sky.
Forty kilometers above the planet, the thin began to slow its fall. Six kilometers above the planet a big parachute(降落伞)opened. The landing craft fell more slowly. Then, three rocket engines . And the landing craft set down on the surface. in the Viking One Lander immediately sent a message to the earth. It said, “I am here. I am down safely. I am beginning my work. ”
The message at the speed of light. It took twenty minutes to reach the earth, more than three hundred and twenty million kilometers . Scientists and engineers at the control center .
Moments later, television receiver in the control center began to the first picture from Viking One. People at the center could see the feet of the landing craft sitting firmly on the 11 soil of Mars. Those pictures were our first look at the planet. They showed a red surface, full of rocks, with no sign of . It was our first look at a planet that is full of surprises, mysteries and promise. Viking One was launched toward Mars in August, 1975. The spaceship had two : an orbiter(轨道飞行器)and a lander(着陆器). The orbiter would circle Mars. It would take pictures of Mars’ surface. It would the atmosphere.
The would go down to the surface. It would carry to dig up and study soil and .
It also would report about any evidence of life on the planet. The lander would send this to the orbiter and then back to the earth.
| 小题1: | | A．separated | B．appeared | | C．worked | D．started |
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| 小题2: | | A．correctly | B．slowly | C．quickly | D．directly |
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| 小题3: | | A．air | B．universe | | C．space | D．atmosphere |
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| 小题4: | | A．fired | B．fell | C．opened | D．floated |
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| 小题5: | | A．heavily | B．softly | | C．suddenly | D．immediately |
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| 小题6: | | A．A computer | B．A rocket | | C．A pilot | D．An astronaut |
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| 小题7: | | A．spread | B．traveled | C．shot | D．moved |
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| 小题8: | | A．far | B．long | C．distant | D．away |
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| 小题9: | | A．shouted | B．watched | | C．cheered | D．welcomed |
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| 小题10: | | A．make | B．take | C．show | D．search |
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| 小题11: | | A．red | B．brown | C．gray | D．black |
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| 小题12: | | A．careful | B．close | C．real | D．clear |
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| 小题14: | | A．parts | B．rockets | C．engines | D．centers |
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| 小题15: | | A．through | B．towards | C．over | D．around |
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| 小题16: | | A．enter | B．examine | | C．collect | D．discover |
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| 小题17: | | A．orbiter | B．lander | | C．spaceship | D．rocket |
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| 小题18: | | A．engineers | B．astronauts | | C．parachutes | D．instruments |
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| 小题19: | | A．surface | B．trees | C．rocks | D．pictures |
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| 小题20: | | A．spaceship | B．rocket | | C．lander | D．information |
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One night in March 1999, a man was driving from California to Oregon, US, to visit some friends. He had stopped his car to have some food when he started to hear strange noises. Turning on the headlights, he saw an 8-foot-tall creature covered in thick, dark hair. The creature stared at him for a minute, turned in the road and walked off slowly into the woods.
In the past 50 years alone, there have been thousands of reported sightings of similar creatures in the US, Canada, the Himalayas(喜马拉雅山地区)and even Hubei Province in China. The creature is known as bigfoot.
Bigfoot is said to be a very tall(between 2 and 4. 5 metres), ape-like(类人猿似的)creature that is covered in hair and walks upright on two legs. It is very wary(警惕的)of human beings.
Believers think bigfoot is a direct descendent(后代)of ancient gigantopithecus(巨猿). But it remains one of the planet’s undiscovered secrets. There is a little evidence(证据)to support the believers’ theory: traces of hair, footprints and body prints as well as the reported sightings. Some people have even showed what they say with photos or films of bigfoot.
But so far, no one has found bones or any other definite proof that the giant creature exists.
As a result many people believe the evidence is just part of a big trick.
The footprints are easy to make and they say: all you need to do is to make two large feet out of plaster(石膏), attach them to the bottom of your shoes and walk with big steps. As for the photos and films, they are just people dressed in ape suits.
They also say the sightings are not real, just people making mistakes. For example, bigfoot could be a bear living in the wild that sometimes stands up on its back legs.
小题1: So far what we can be sure about is that . | A．there exist savages(野人)in several places in the world | | B．there are some traces of hair, footprints and body prints of the “bigfoot” | | C．bigfoot is a direct descendent of ancient gigantopithecus | | D．all the big foot discovered have the same look |
小题2:It was in that man first found the ape-like creature. | A．1999 | B．the 1960’s | | C．the 1950’s | D．the 1940’s |
小题3: The article infers but doesn’t say so that some people bigfoot’s existence. | A．may fool the world into believing | | B．have definite evidences to prove | | C．refuse to believe | | D．will soon offer proofs of |
小题4:If bigfoot is just a misunderstanding, what they saw might NOT be . | A．apes | | B．bears | | C．gigantopithecus | | D．people dressed in animal skins |
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