Mars Was Not Always Bitterly ColdScientists at the California Institute of Techn
题型：不详难度：来源：
Mars Was Not Always Bitterly Cold
Scientists at the California Institute of Technology (Caltech) have reported evidence that Mars was warmer and wetter long ago than it is today. The Caltech scientists say they have directly established the temperature of Mars four billion years ago. At least, they established the surface temperature on part of the planet at that time. The researchers say it is the first such evidence to be discovered and presented.
The Caltech scientists say carbonate（碳酸盐） minerals formed on Mars at about eighteen degrees Celsius. They reached the finding after studying a meteorite（陨石） that had its beginnings near the Martian surface.
Today, the average temperature on Mars is sixty-three degrees below zero Celsius.
The finding was reported on the website of the National Academy of Sciences. Caltech Assistant Professor Woody Fischer helped to prepare the report. He says eighteen degrees Celsius is not especially cold or hot. He says this makes the finding extremely interesting. Knowing the temperature can give scientists an idea of the climate on Mars long ago. It can also help them decide whether the planet had liquid water. Spacecraft orbiting Mars have shown what appear to be rivers, lakebeds and mineral deposits. These pictures suggest that, at one time, water did flow there. Mars Rover vehicles and other spacecraft have confirmed the information.
Caltech Geology Professor John Eiler was another writer of the report. He says knowing the temperature of Mars from long ago provides valuable information. It shows that early in the planet"s history, at least part of Mars could support a climate like that of Earth.
The meteorite the scientists examined is one of the oldest known rocks in the world. It is called the Allan Hills meteorite. Its name came from the place in Antarctica where it was found in 1984. The meteorite is believed to have blown loose from the Mars" surface when another space rock struck its "home."
小题1: The underlined word “establish” in Paragraph 1 probably means “___________”.| A．to set up | | B．to make people accept a belief | | C．to discover or prove | | D．to start having a relationship with others |
小题2:How did the scientists reach the finding?| A．By studying Allan Hills meteorite. | | B．By using spacecraft orbiting Mars. | | C．By studying minerals gathered on Mars | | D．By studying a meteorite on the Martian surface. |
小题3:According to the fourth paragraph, what have spacecraft orbiting Mars done?| A．Measuring the temperature of Mars. | | B．Taking photos of the surface of Mars. | | C．Confirming that there is water flowing on Mars. | | D．Finding where human beings will probably land on Mars. |
小题4:How did Allan Hills meteorite get its name?| A．From its original place on Mars. | | B．From where it was found on the earth. | | C．From the name of the scientist who found it. | | D．From the name of the aircraft that discovered it |
小题5: Where can we most probably read this passage?| A．In a biography of scientists. | | B．In a geography magazine. | | C．In an environment report. | | D．In a science report. |
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答案
小题1:C
小题2:A
小题3:B
小题4:B
小题5:D |
解析
试题分析：
小题1:从第一段最后一句The researchers say it is the first such evidence to be discovered and presented结合前面两句可以说明科学家发现了40亿年前的火星地表的温度的证据。
小题2:从第二段They reached the finding after studying a meteorite（陨石） that had its beginnings near the Martian surface.及最后一段It is called the Allan Hills meteorite可知答案A, D答案错在on the surface.
小题3:从第四段倒数第二，三可以看出宇宙飞船火星轨道是给火星地表拍照的。
小题4:从最后一段Its name came from the place in Antarctica where it was found in 1984可知正确答案。
小题5:从第一段第一句可知本文主要讲的是一个科学报告，故选Ｄ
点评：本文主要说明一个科学报告：许多年前火星比现在更温暖，潮湿。科普说明文要注意首段首句，往往会在首句点明一个科学研究发现。 |
举一反三
Today just as technology changed the face of industry, farms have undergone an “agricultural revolution”. On the farm of today, machines provide almost all the power.
One of the most important benefits will be the farm computer. A few forward-looking farmers are already using computers to help them run their farms more efficiently. The computers help them keep more accurate records so they can make better decisions on what crops to plant, how much livestock to buy, when to sell their products, and how much profit they can expect. Many computer companies have been developing special computer programs just for farmers. Programs are being written for hog producers, grain farmers, potato farmers, and dairy farmers. In the future, farmers will be able to purchase computer programs made to their needs. Because of the growing importance of computers on the farm, students at agricultural colleges are required to take computer classes in addition to their normal agricultural courses. There can be no doubt that farmers will rely on computers even more in the future. While the old-time farm depended on horse power, and modern farms depend on machine power, farms of the future will depend on computer power.
Another technological advance which is still in the experimental stage is the robot, a real “mechanized hired hand” that will be able to move and, in some ways, think like a human being. Agricultural engineers believe that computer-aided robots will make startling changes in farming before the end of the century. Unlike farmers of the present, farmers of the future will find that many day-to-day tasks will be done for them. Scientists are now developing robots that will be able to shear sheep, drive tractors, and harvest fruit. Even complex jobs will be done by robots. For example, in order to milk their cows, farmers must first drive them into the barn, then connect them to the milking machines, watch the machines, and disconnect them when they are finished. In the future, this will all be done by robots. In addition, when the milking is completed, the robots will automatically check to make sure that the milk is pure. The complete mobilization of the farm is far in the future, but engineers expect that some robots will be used before long.
小题1:Which sentence carried the main idea of the whole passage?| A．The first sentence of the first paragraph. | | B．The first sentence of the second paragraph. | | C．The first sentence of the third paragraph. | | D．The last sentence of the second paragraph. |
小题2: according to the passage, computers can not help farmers decide _______.| A．how much money they can earn from their products | | B．whether to plant a certain kind of crop | | C．what livestock to raise | | D．when to sell their products |
小题3:Which of the following statements is true?| A．Farmers in the future will depend totally on computers. | | B．Both computers and robots have been in use on today’s farms. | | C．Farmers mainly use machines on their farms at present. | | D．Students at agricultural colleges must take computer classes because they can do nothing without the help of computers on today’s farms. |
小题4:according to the engineers, _______will be done by robots in the near future.| A．all farm work | B．milking cows | | C．most of the farm work | D．some farm work |
小题5:What is the best title for the whole passage?| A．Computer, Farmers’ Best Friend | B．Farmers in The Future | | C．The Agricultural Revolution | D．Computers and Robots |
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It’s good to make mistakes, and here is why．
First of all, mistakes are a clear sign that you are trying new things． It’s always good to try new things because when you are trying new things you are growing． If you never try anything new, how can you improve? How can you expand? The simple answer is “You can’t”． Look around you． With very few exceptions, either everything you see in your physical world or every single detail of every single thing is the result of someone trying something new．
Another good thing about mistakes is this: When you are making mistakes, you are learning． Consider this: Edison failed 10,000 times before he perfected the light bulb． When asked how it felt to fail that many times, he said that he hadn’t failed 10,000 times, but rather had learned 10,000 things that didn’t work．
Finally, when you make a mistake you are much closer to success． Why?
Because when all is said and done, you will have tried some number of things before you succeeded． Every time you make a mistake you eliminate one of those things and are one step closer．
But this all doesn’t mean that you should go ahead without considering the consequences of a mistake． Quite the contrary, when you try something new you have to be willing to set some reasonable limits so that in the event that it doesn’t work out the way you want it to, you will be in a position to try again．
We all have limited resources in the form of time and money so don’t blow them all on one approach to a problem． Realize that it probably won’t be perfect the first time and allocate （分配） these resources appropriately so you can learn, make corrections, and try it again． Only by accepting and using your mistakes in this way can you make significant advances in your business and your career．
There is an old saying that goes, “If you’re not making mistakes, you’re not trying hard enough．”
So go forth and make mistakes． And learn． And grow． And prosper（成功）．
小题1:From the second paragraph, we can conclude that _______．| A．mistakes are unnecessary for development | | B．we are afraid of trying new things | | C．it’s common for people to make mistakes | | D．mistakes are better than not trying |
小题2:The underlined word “eliminate” means _______．| A．avoid | B．remove | C．accept | D．solve |
小题3:According to the article, one thing you should pay attention to about making mistakes is ．| A．avoiding making the same mistakes | | B．accepting the punishment willingly | | C．taking consequences into account | | D．trying things out one by one |
小题4:What would the writer probably suggest we say to ourselves when we make a mistake?| A．Never mind, I can always try again． | | B．I’d better stay out of trouble． | | C．Ok! Now I can learn something． | | D．Look at this mess． Anyone would be upset． |
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A new study says one part of the human brain may become smaller as the result of a condition known as jet lag. Jet lag results from flying long distances in an airplane. People with jet lag may feel extremely tired for several days. They may also have problems thinking clearly and remembering.
Recently a researcher at the University of Bristol in Britain reported the findings of his jet lag study, which involved twenty young women who worked for international airlines. They had served passengers on airplanes for five years. These flight attendants flew across many countries and at least seven time zones. In the study, the flight attendants had different amounts of time to recover from jet lag. Half the women spent five days or fewer in their home areas between long flights. The other half spent more than fourteen days in their home areas.
The researcher took some saliva from the women”s mouths to measure levels of a hormone(荷尔蒙) that increases during stress(紧张). He tested them to see if they could remember where black spots appeared on a computer screen. And he took pictures of their brains to measure the size of the brain”s temporal lobes(脑叶).
It was found that the women who had less time between flights had smaller right temporal lobes. This area of the brain deals with recognizing and remembering what is seen. The same group performed worse and had slower reaction times on the visual memory test. And their saliva samples showed higher levels of stress hormones.
The researcher believes the brain needs at least ten days to recover after a long trip. He says airline workers told him their ability to remember got worse after working on planes for about four years. Other studies have shown that increased feelings of stress can cause a loss of cells in the part of the brain that controls memory.
Scientists say more tests are needed to study the effects of jet lag on the brain. They want to find out if too much jet lag could permanently (永久性的) affect memory.
小题1:According to the text, jet lag .
- can cause difficulties in speaking
- can make people feel tired for a few weeks
- can be only found in flight attendants
- can be caused by flying over several time zones
小题2:It can be inferred from the text that .
- the conclusion is refused by many scientists
- scientists fear that this research is not doneproperly
- the scientific conclusion needs the support frommany tests
- every women who were examined in the research weremot healthy
小题3:From the result of the research we can see that .
- the women who have longer rest at home show better memory
- the women who fly in short time have smaller righttemporal lobes
- the women who have longer flights fail the memorytest
- the women who rest more than 14 days produce lesshormones
小题4:What is the subject discussed in the text?
- The cause of jet lag.
- A story of a group of flight attendants.
- The importance of having enough rest after flights.
- A research about the effects of jet lag on thebrain.
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Now let us look at how we read. When we read a printed text, our eyes move across a page in short, jerky movement. We recognize words usually when our eyes are still when they fixate. Each time they fixate, we see a group of words. This is known as the recognition span or the visual span. The length of time in which the eyes stop ---the duration of the fixation ----varies considerably from person to person. It also varies within any one person according to his purpose in reading and his familiarity with the text. Furthermore, it can be affected by such factors as lighting and tiredness.
Unfortunately, in the past, many reading improvement courses have concentrated too much on how our eyes move across the printed page. As a result of this misleading emphasis on the purely visual aspects of reading, numerous exercises have been devised to train the eyes to see more words at one fixation. For instance, in some exercises, words are flashed on to a screen for, say, a tenth or a twentieth of a second. One of the exercises has required students to fix their eyes on some central point, taking in the words on either side. Such word patterns are often constructed in the shape of rather steep pyramids so the reader takes in more and more words at each successive fixation. All these exercises are very clever, but it’s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently. Reading requires the ability to understand the relationship between words. Consequently, for these reasons, many experts have now begun to question the usefulness of eye training, especially since any approach which trains a person to read isolated words and phrases would seem unlikely to help him in reading a continuous text.
小题1:The time of the recognition span can be affected by the following facts except ________ .| A．the length of a group of words. | | B．lighting and tiredness. | | C．one’s familiarity with the text. | | D．one’s purpose in reading. |
小题2:The author may believe that reading ______.| A．demands an deeply-participating mind. | | B．demands more mind than eyes. | | C．requires a reader to take in more words at each fixation. | | D．requires a reader to see words more quickly. |
小题3:What does the author mean by saying “but it’s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently.” in the second paragraph?| A．The reading exercises mentioned can’t help to improve an efficient reading. | | B．The reading exercises mentioned has done a great job to improve one’s ability to see words. | | C．The ability to see words is not needed when an efficient reading is conducted. | | D．The reading exercises mentioned can’t help to improve both the ability to see or comprehend words. |
小题4:Which of the following is NOT true?| A．The emphasis on the purely visual aspects is misleading. | | B．The eye training will help readers in reading a continuous text. | | C．The visual span is a word or a group of words we see each time. | | D．Many experts began to question the efficiency of eye training. |
小题5:The tune of the author in writing this article is ________.| A．pessimistic | B．optimistic | C．critical | D．neutral |
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A friend of mine met with an accident driving in darkness. His legs were so hurt that he couldn’t move. What was the 1 was that he found himself unable to ask for help—his mobile phone went out of 2 as a result of exhausted battery (无电) . Nothing could be done but to 3 in cold wilderness (荒野). It was eight hours later that day broke, and then 4 of the rescue (援救).
It is almost 5 that he could stand （忍受）the horror in the darkness for so long. Even more surprising was his 6 : “First of all, I checked up my 7 conditions and found myself not in mortal (致命的) danger. As there was no 8 to call for help, I leaned back in my seat trying my best to keep the wound from 9 . In this way I dozed (瞌睡) off.”
His story put an end to my regret (遗憾) for the 10 of an exploration adventure (探险) that happened last year. A group of young men 11 to explore a mountain cave and got lost. 12 to find a way out in the dark cave they were frightened and ran anxiously without a sense of 13 . Finally they felt dead in fear and exhaustion. According to the 14 people that found them, the place where they got lost was only about 10 meters away from the 15 of the cave. If they stayed on the spot when they lost their way and tried to 16 themselves, they would probably sense a faint light glimmering (闪烁) not far away.
Don’t you think you can compare it with 17 itself? When you meet with difficulty in life and work, you are lost in darkness. 18 you it’s unclear yet and you needn’t put up struggle 19 . It seems to be a negative （消极）attitude, 20 a person who can afford to do so must have foresight (远见) as well as a great courage in the first place.
| 小题1: | | A．hopeless | B．worst | C．more | D．best |
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| 小题2: | | A．service | B．way | C．control | D．work |
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| 小题4: | | A．delay | B．success | C．team | D．arrival |
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| 小题5: | | A．untrue | B．unimaginable | C．true | D．useless |
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| 小题6: | | A．plan | B．decision | C．explanation | D．excuse |
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| 小题7: | | A．physical | B．mental | C．working | D．medical |
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| 小题8: | | A．energy | B．way | C．tools | D．strength |
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| 小题9: | | A．rotting | B．spreading | C．hurting | D．bleeding |
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| 小题10: | | A．loss | B．failure | C．disappointment | D．sadness |
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| 小题11: | | A．had | B．managed | C．tried | D．meant |
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| 小题12: | | A．Willing | B．Unable | C．Determined | D．Deciding |
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| 小题13: | | A．hearing | B．sight | C．feeling | D．direction |
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| 小题14: | | A．rescue | B．village | C．local | D．brave |
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| 小题15: | | A．end | B．top | C．opening | D．side |
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| 小题17: | | A．adventure | B．work | C．life | D．mankind |
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| 小题18: | | A．Mind | B．Watch | C．Imagine | D．Warn |
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| 小题19: | | A．really | B．immediately | C．carefully | D．hopefully |
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