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科目: 來(lái)源:遼寧省沈陽(yáng)市2010屆高三下學(xué)期教學(xué)質(zhì)量監(jiān)測(cè)(二) 題型:閱讀理解


D
Is a recently discovered hormone the reason why folks who lose weight can’t keep it off?
Like millions of other fat people, at 530 inches high, more than 300 pounds, Carnie Wilson was not just fat. After trying all sort of diets that didn’t work, she has to go to the stomach – bypass surgery (胃部迂回手術(shù)), ie, have most of her stomach sewed up, only leaving tiny room to hold several tablespoonfuls at most. Result: she simply couldn’t eat the way she used to. In three years, Wilson is one third of her former weight.
Wilson’s experience is not all that unusual, and while doctors still aren’t exactly sure what is going on, a report in last week’s Journal of Medicine offers an explanation. The loss of appetite in bypass patients may be linked to a recently discovered hormone called ghrelin. Not only that, ghrelin may turn out to be one reason we feel hungry and it’s hare for didters to keep weight off.
Nowadays, researchers are careful to stress only what they know for sure. For the three conclusions, the leading Dr. David of the University of Washington says, “I feel very solid about two of them.” The first is that ghrelin levels in the bloodstream rise significantly before meals and drop afterward. The second conclusion is that ghrelin levels are higher on average in people who have lost weight from dieting.
Dr. David is less sure of the third conclusion, that bypass patients have only a quarter as much ghrelin as most people of normal weight. After all, ghrelin is produced by cells in the stomach. Years ago, leptin, a hormone was found as an appetite suppressant (食物抑制劑). But after years of trying, it had to be given up.
What doctors suspect is that both leptin and ghrelin are part of a complex system of brain and body chemicals that govern weight and appetite. That does not mena pharmaceutical (藥物的) weight control is forever out of the question. “In the next ten years, we will be able to develop new drugs to help people lose weight healthily and effectively.”
47.What can we learn about ghrelin according to the passage?
A.After meals ghrelin levels are higher in the bloodstream.
B.People who have lost weight have less ghreilin in their body.
C.Without ghrelin, people are really difficult to lose weight.
D.Ghrelin is something produced by cells in the stomach.
48.What is Dr. David not sure?
A.pharmaceutical weight control is impossible.
       B.There is less ghrelin in the bypass patients.
C.new drugs will be developed in 10 years.
D.ghrelin levels are higher in people on diet.
49.In fact, people’s weight and appetite are controlled by        
A.ghrelin and leptin                      B.hormone and medicine
C.brain and body chemicals                  D.stomach and food
50.What can we infer from the passage?
A.People with a lower ghrelin level go hungry easily.
B.Doctors managed to use leption to control the appetite.
C.Doctors are optimistic about how to lose weight healthily.
D.The loss of appetite in bypass aptient is linked to leptin

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科目: 來(lái)源:北京市崇文區(qū)2010屆高三下學(xué)期統(tǒng)一練習(xí)(一) 題型:閱讀理解


D
The recent, apparently successful, prediction by mathematical models of an appearance of El Nino—the warm ocean How that periodically develops along the Pacific coast of South America has excited researchers.Jacob Bjerknes pointed out years ago how winds might create either abnormally warm or abnormally cold water in the eastern equatorial (赤道附近的) Pacific.Nevertheless, before the creation of the models, no one could explain why conditions should regularly change between appearances of the warm El Nino and the so-called anti-El Nino.The answer, at least if the current model that links the behavior of the ocean to that of the atmosphere is correct, is to be found in the ocean.
It has long been known that during an El Nino, two conditions exist: unusually warm water extends along the eastern Pacific and winds blow from the west into the warmer air rising over the warm water in the east.The contribution of the model is to show that the winds of an El Nino, which raise sea level in the east, send a signal to the west lowering sea level at the same time.According to the model, that signal is created as a negative (負(fù)的) Rossby wave, a wave of lower sea level, that moves westward parallel to the equator at 25 to 85 kilometers per day.Taking months to move across the Pacific, Rossby waves march to the western boundary of the Pacific basin, which is modeled as a smootli wall but in reality consists of quite irregular island chains.
When the waves meet the western boundary, they are reflected, and the model predicts that Rossby waves will be broken into many coastal Kelvin waves carrying the same negative sea-level signal.These eventually shoot toward the equator, and then head eastward along the equator drove by the earth at a.speed of about.250 kilometers per day.When enough Kelvin waves of adequate amplitude (振幅) arrive from the western Pacific, their negative sea-level signal overcomes the feedback mechanism, raising the sea level, and they begin to drive the system into the opposite cold mode.This produces a gradual change in winds, one that will eventually send positive sea-level Rossby waves westward, waves that will eventually return as cold cycle—ending positive Kelvin waves beginning another warming cycle.
67.What is the passage mainly about?
A.How Rossby waves are found.
B.Where El Nino is formed.
C.What the models predict.
D.How the models work.
68.Where does El Nino often appear?
A.Along the western coast of the USA .
B.In the Pacific in the south, of the equator.
C.In the Pacific in the north of the equator.
D.Along the southern coast of South America.
69.What is right according to the passage?
A.Rossby waves and Kelvin waves move in opposite directions along the equator.
B.People could explain El Nino before the creation of the mathematical models.
C.Adequate sea-level waves can produce westward positive cold cycle.
D.The speed of Rossby waves is faster than that of Kelvin waves.
70.What does the underlined word "waves" in Paragraph 3 refer to?
A.Kelvin waves.       B.Sea-level signals.   C.Coastal waves.   D.Rossby waves.

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科目: 來(lái)源:北京市崇文區(qū)2010屆高三下學(xué)期統(tǒng)一練習(xí)(一) 題型:閱讀理解


C
Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years, but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once, but they cannot read or write.
Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment (損傷) , such as in autism or retardation.At the same time, the person also exhibits some extraordinary skills, which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics, or having a photographic memory.
One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient, Thomas Fuller, was brought to Virginia as a slave in 1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years, 17 days, and 12 hours has lived 2,210,500,800 seconds.Despite this ability, he died in 1790 without ever learning to read or write.
Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words, but he played 5 ,000 musical pieces beautifully.
In the excellent movie Rain Man, made in 1988 and available on video cassette, Dustin Hoffman plays an idiot savant who amazes his brother played by Tom Cruise, with his ability to perform complex calculations very rapidly.
Today we more clearly recognize that the idiot savant is special because of brain impairment.Yet not all brain impairment leads to savant skills.Some studies have shown that people who have purposeful interruption of the left side of the brain can develop idiot savant skills.However few people wish to participate in such experiments.There are many excellent reasons for not undergoing unnecessary experimentation on one's brain.The term idiot savant is outdated and inappropriate.Virtually all savants have a high degree of intelligence and are thus not idiots.
63.What does the passage mainly talk about?
A.Idiot savants have areas of outstanding abilities.
B.Human Beings have complicated thinking process.
C.The brains of the idiot savants are partly impaired.
D.The reasons why people have wonderful skills vary.
64.Which of the following can be done by Rain Man?
A.He can play wonderful pieces of classical music.
B.He can guess out exactly the length of a man's life.
C.He can memorize the contents of the pictures fast.
D.He can count matches dropped on the floor quickly.
65.What can you infer from the passage?
A.Idiot savants have real talents for art and math.
B.Dr.Down is the first person who found idiot savants.
C.Few people wish to risk becoming savants by brain operations.
D.Intentional left brain impairments will surely lead to idiot savants.
66.Which of the following shows the structure of the passage?

1—5refer to paragraph 1—5.

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科目: 來(lái)源:山東省2009-2010學(xué)年度高一上學(xué)期學(xué)分認(rèn)定考試 題型:閱讀理解


C
Why do men die earlier than women? The latest research makes it known that the reason could be that men’s hearts go into rapid decline when they reach middle age.
The largest study of the effects of ageing on the heart has found that women’s longevity may be linked to the fact that their hearts do not lose their pumping power with age.
“We have found that the power of the male heart falls by 20-25 percent between 18 and 70 years of age,” said the head of the study, David Goldspink of Liverpool John Moores University in the UK.
“Within the heart there are millions of cells that enable it to beat. Between the age of 20 and 70, one-third of those cells die and are not replaced in men,” said Goldspink. “This is part of the ageing process.”
What surprises scientists is that the female heart sees very little loss of these cells. A healthy 70-year-old woman’s heart could perform almost as well as a 20-year-old one’s.
“This gender difference might just explain why women live longer than men,” said Goldspink. They studied more than 250 healthy men and women between the ages of 18 and 80, focusing on healthy persons to remove the confusing influence of disease. “The team has yet to find why ageing takes a greater loss on the male heart,” said Goldspink.
The good news is that men can improve the health of their heart with regular exercise. Goldspink stressed that women also need regular exercise to prevent their leg muscles becoming smaller and weaker as they age.
69. The underlined word “l(fā)ongevity” in the second paragraph probably refers to “________”.
A. health          B. long life         C. ageing         D. effect
70. The text mainly talks about ________.
A. men’s heart cells                    B. women’s ageing process
C. the gender difference                D. hearts and long life
71. According to the text, the UK scientists have known that ________.
A. women have more cells than men when they are born
B. women can replace the cells that enable the heart to beat
C. the female heart loses few of the cells with age
D. women never lose their pumping power with age
72. If you want to live longer, you should ________.
A. enable your heart to beat much faster
B. find out the reason for ageing
C. exercise regularly to keep your heart healthy
D. prevent your cells from being lost

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科目: 來(lái)源:河北省冀州中學(xué)2010屆高三下學(xué)期第一次月考 題型:閱讀理解


D
Gauri Nanda sees a wearable computer as a handbag—one that’s built out of four-inch squares and triangles of fiber, with tiny computer chips embedded(嵌入) in it. It looks, feels and weighs like your typical leather purse.
That’s where similarities end: This bag can wirelessly keep track of your belongings and
remind you, just as you’re about to leave the house, to take your wallet. It can review the weather report and suggest that you grab an umbrella. This purse can even upload your favorite songs onto your scarf.
Sure, a computing purse and scarf set may seem like the stuff of science fiction. But these devices, part of next generation of wearable computers, could become commonplace within a few years. DuPont created new super strong fibers that can conduct electricity and can be woven into ordinary-looking clothes. And the chipmaker developed chip packaging allowing wearable computers to be washed, even in the heavy-duty cycle.
As a result, these new wearable devices are different from the heavy and downright silly versions of the recent past, which often required users to be wrapped in wires and type on their stomachs. Unlike their predecessors, these new wearable computers also make economic sense. When her bag becomes commercially available in two to three years, Nanda expects it will cost around $150, which is the price of an average leather purse.
Here’s how the bag works: You place a special radio-signal-transmitting chip on to your wallet. A similar radio in your purse picks up the signal and notifies you that you’ve forgotten to take your wallet. In turn, sensors on your purse’s handles will notify the computer that you’ve picked up the purse and are ready to go.
Already, these new kinds of wearable devices are being adopted for use in markets like auto repair, emergency services, medical monitoring—and even, increasingly, for consumers at large. Indeed, more people will want to cross that bridge in the coming years--- making for a booming market for wearable computers that don’t like something out of science fiction.
52. Which of the following describes a wearable computer?
A. It can be washed in a washing machine.
B. It is much heavier than a leather purse.
C. It can download songs from the Internet.
D. It is made of clothes conducting electricity.
53. According to the passage, these new wearable computers ______.
A. require users to operate on the stomach
B. pick up the signals through wires and chip
C. are being applied in some different areas now
D. are smarter but more expensive than the old ones
54. What does the underlined sentence in the last paragraph mean?
A. These new wearable computers have become fashionable.
B. People would like to learn more about these new computers.
C. These new wearable computers promise to sell well in the future.
D. The idea of these purse-like computers comes from science fiction.
55. The purpose of the passage is ______.
A. to introduce a new kind of computer                     B. to explain the function of computers
C. to compare different types of computers      D. to show how high technology affects our life

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科目: 來(lái)源:2010屆江蘇省揚(yáng)州市高三第二次模擬考試英語(yǔ)試題 題型:閱讀理解

任務(wù)型閱讀 (共10小題;每小題1分,滿分10分)
請(qǐng)認(rèn)真閱讀下列短文,并根據(jù)所讀內(nèi)容在文章后表格中的空格里填入一個(gè)最恰當(dāng)?shù)膯卧~。
注意:每個(gè)空格只填1個(gè)單詞。請(qǐng)將答案寫在答題卡上相應(yīng)題號(hào)的橫線上。
Waste to Energy—JUST BURN IT!
WHY BURN WASTE?
Waste-to-energy plants generate (產(chǎn)生) enough electricity to supply 2.4 million households in the US. But, providing electricity is not the major advantage of waste-to-energy plants. In fact, it costs more to generate electricity at a waste-to-energy plant than it does at a coal, nuclear, or hydropower plant. 
The major advantage of burning waste is that it considerably reduces the amount of trash going to landfills. The average American produces more than 1,600 pounds of waste a year. If all this waste were landfilled, it would take more than two cubic yards of landfill space. That’s the volume of a box three feet long, three feet wide, and six feet high. If that waste were burned, the ashes would fit into a box three feet long, three feet wide, but only nine inches high!
Some communities in the Northeast may be running out of land for new landfills. And, since most people don’t want landfills in their backyards, it has become more difficult to obtain permits to build new landfills. Taking the country as a whole, the United States has plenty of open space, of course, but it is expensive to transport garbage a long distance to put it into a landfill.
TO BURN OR NOT TO BURN?
Some people are concerned that burning garbage may harm the environment. Like coal plants, waste-to-energy plants produce air pollution when the fuel is burned to produce steam or electricity. Burning garbage releases the chemicals and substances found in the waste. Some chemicals can be a threat to people, the environment, or both, if they are not properly controlled.
Some critics of waste-to-energy plants are afraid that burning waste will hamper (妨礙,阻礙) recycling programs. If everyone sends their trash to a waste-to-energy plant, they say, there will be little motive to recycle. Several states have considered or are considering banning waste-to-energy plants unless recycling programs are in place. Massachusetts, New Jersey, and New York City have delayed new waste-to-energy plants, hoping to increase the level of recycling first.
So, what’s the real story? Can recycling and burning waste coexist? At first glance, recycling and waste-to-energy seem to be at odds (不一致), but they can actually complement (彌補(bǔ)) each other. That’s because it makes good sense to recycle some materials, and better sense to burn others.
Let’s look at aluminum, for example. Aluminum mineral is so expensive to mine that recycling aluminum more than pays for itself. Burning it produces no energy. So clearly, aluminum is valuable to recycle and not useful to burn.  
Paper, on the other hand, can either be burned or recycled—it all depends on the price the used paper will bring.
Plastics are another matter. Because plastics are made from petroleum and natural gas, they are excellent sources of energy for waste-to-energy plants. This is especially true since plastics are not as easy to recycle as steel, aluminum, or paper. Plastics almost always have to be hand sorted and making a product from recycled plastics may cost more than making it from new materials. 
To burn or not to burn is not really the question. We should use both recycling and waste-to-energy as alternatives to landfilling.
Waste to Energy—JUST BURN IT!

WHY BURN WASTE?
Advantages of waste to Energy
◆Though at a high (71) _______, waste-to-energy plants can produce enough electricity for 2.4 million US
households.
◆Burning waste can (72) _______ a considerable amount of trash going to landfills.
(73)_______ for landfilling
◆Some communities (74) _______ land for new landfills.
◆Most people refuse to build landfills around.
◆Building landfills in far-away areas will increase the cost of (75) _______ garbage.
TO BURN
OR NOT
TO BURN?
(76) __________ about burning garbage
◆Burning garbage releases chemicals, which, if not
properly controlled, can be (77) _______ to people and the environment.
◆Burning garbage will hamper recycling programs.
Coexistence of recycling and burning waste
Recycling and waste-to-energy can go well with each other in that some materials like aluminum are fit to recycle, while others like plastics are fit to (78) _______.
(79)__________
Whether to burn or not to burn, we should (80) _______ landfilling with both recycling and waste-to-energy to deal with garbage.

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科目: 來(lái)源:2010屆江蘇省揚(yáng)州市高三第二次模擬考試英語(yǔ)試題 題型:閱讀理解

Saving the Planet with Earth-Friendly Bamboo Products
Jackie Heinricher’s love affair with bamboo started in her backyard. “As a child, I remember playing among the golden bamboo my dad had planted, and when there was a slight wind, the bamboos sounded really musical.”
A fisheries biologist, Heinricher, 47, planned to work in the salmon industry in Seattle, where she lived with her husband, Guy Thornburgh, but she found it too competitive. Then her garden gave her the idea for a business: She’d planted 20 bamboo forests on their seven-acre farm. 
Heinricher started Boo-Shoot Gardens in 1998. She realized early on what is just now beginning to be known to the rest of the world. It can be used to make fishing poles, skateboards, buildings, furniture, floors, and even clothing. An added bonus: Bamboo absorbs four times as much carbon dioxide as a group of hardwood trees and releases 35 percent more oxygen.
First she had to find a way to mass-produce the plants—a tough task, since bamboo flowers create seed only once every 50 to 100 years. And dividing a bamboo plant frequently kills it.
Heinricher appealed to Randy Burr, a tissue culture expert, to help her. “People kept telling us we’d never figure it out,” says Heinricher. “Others had worked on it for 27 years! I believed in what we were doing, though, so I just kept going.”
She was right to feel a sense of urgency. Bamboo forests are being rapidly used up, and a United Nations report showed that even though bamboo is highly renewable, as many as half of the world’s species are threatened with dying out. Heinricher knew that bamboo could make a significant impact on carbon emissions (排放) and world economies, but only if huge numbers could be produced. And that’s just what she and Burr figured out after nine years of experiments—a way to grow millions of plants. By placing cuttings in test tubes with salts, vitamins, plant hormones, and seaweed gel, they got the plants to grow and then raised them in soil in greenhouses.
Not long after it, Burr’s lab hit financial difficulties. Heinricher had no experience running a tissue culture operation, but she wasn’t prepared to quit. So she bought the lab.
Today Heinricher heads up a profitable multimillion-dollar company, working on species from all over the world and selling them to wholesalers. “If you want to farm bamboo, it’s hard to do without the young plants, and that’s what we have,” she says proudly.
56. What was the main problem with planting bamboo widely?
A. They didn’t have enough young bamboo.
B. They were short of money and experience.
C. They didn’t have a big enough farm to do it.
D. They were not understood by other people.
57. What does Heinricher think of bamboo?
A. Renewable and acceptable                             B. Productive and flexible.
C. Useful and earth-friendly.                                 D. Strong and profitable.
58. The underlined word “renewable” in Paragraph 6 probably means “________”.
A. able to be replaced naturally                B. able to be raised difficultly
C. able to be shaped easily                    D. able to be recycled conveniently
59. What do you learn from the passage?
A. Heinricher’s love for bamboo led to her experiments in the lab.
B. Heinricher’s determination helped her to succeed in her work.
C. Heinricher struggled to prevent bamboo from disappearing.
D. Heinricher finally succeeded in realizing her childhood dream.

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科目: 來(lái)源:黑龍江省鶴崗一中2009-2010學(xué)年度高一下學(xué)期開學(xué)測(cè)試 題型:閱讀理解


C
Will it matter if you don’t take your breakfast?A short time ago,a test was given in the United States.People of different ages from 12 to 83 were asked to have a test.During the test,these people were given all kinds of breakfasts,and sometimes they got no breakfast at all.Scientists wanted to see how well their body worked when they had eaten different kinds of breakfasts.
The results show that if he or she eats a right breakfast,he or she will work better than if he or she has no breakfast.If a student has fruit,eggs,bread and milk before going to school,he will learn more quickly and listen more carefully in class.
The result is opposite to what some people think.Having no breakfast will not help you lose weight.This is because people become so hungry at noon that they eat too much for lunch.They will gain weight instead of losing it.You will lose more weight if you reduce your other meals.
64.During the test,the people were given          .
A.no breakfast at all   B.very rich breakfast
C.different foods or sometimes none   D.little food for breakfast
65.The results show that          .
A.breakfast has little to do with a person’s work
B.breakfast has a great effect on work and studies
C.a person will work better if he only was fruit and milk
D.girl students should have less for breakfast
66.Which of the following is NOT true?
A.It is bad for your health to have no breakfast
B.Too little for breakfast and too much for lunch may make you fatter
C.If you don’t eat much for lunch and supper,you may lose weight
D.The more breakfast you have,the more quickly you’ll learn in class

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科目: 來(lái)源:山東省2010屆高考下學(xué)期模擬考試(一) 題型:閱讀理解


第三部分:閱讀理解(共20小題,每題2分,滿分40分)
閱讀下列短文,從每題所給的四個(gè)選項(xiàng)(A、B、C和D)中,選出最佳選項(xiàng),并在答題卡上將該項(xiàng)涂黑。
A
We bet that on cold wintry days, many of you love to stay in your warm home and, every now and then, come out into the kitchen for a snack. Unfortunately, plenty of creepy-crawly critters(爬行生物) like to do the same thing!
Winter is the time when bugs (蟲子) invade your house without an invitation. The season can be tough for such creatures. In winter the air is cold, the ground is hard and many trees have no leaves. So bugs do what they have to do to survive.
Monarch butterflies head south to warmer climates. Ants crowd in deep underground colonies and eat food they have been storing all year. Many insects go into a deep sleep called diapause. There’re different kinds of diapause, but all are similar to hibernation, a time when bigger animals become inactive in the cold. Insects go into an inactive period, too, but it often isn’t when the temperature drops.
They rely on more dependable signals in the environment. For example, many insects can tell how much sunlight there’s each day. They use that to tell them when to shut down. Bugs are cold-blooded, meaning that their inside temperature is the same as the outside. They can’t move much when it gets below 40 degrees Fahrenheit. So they search for any warm place.
They’re looking for protection. These guys have been doing this for 300 million years, so they don’t really know they’re coming into your house. The home is a recent event in terms of their evolutionary behavior. They enter through tiny cracks or come in unnoticed on your clothes or shoes. Remember that they may be invading your homes for warmth and food, but they don’t care about humans.
56. What is the purpose of the first paragraph?
A. To point out that humans like to stay at home in winter.
B. To mean that humans and bugs have the same living habits.
C. To mean that bugs will invade the house for their winter.
D. To put forward the idea that bugs are not welcome in winter.
57. According to the text, what is diapause?
A. It is the same as the animals’ hibernation.
B. It often appears in warm areas all the year.
C. It is done to keep bugs active in winter.
D. It is a deep sleep similar to hibernation.
58. What often decides bugs’ diapause?
A. The lower local temperatures.           B. The amounts of sunlight.
C. Kinds of environmental signals.         D. The insects’ inside temperature.
59. According to the text, bugs invade humans’ homes to ______.
A. attack humans                                 B. look for enough food
C. seek for protection                           D. show their evolutionary results
60. What would be the best title for the text?
A. Bugs’ life on cold wintry days
B. Why bugs invade your home in winter?
C. Good relations between humans and bugs
D. What does diapause mean?

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科目: 來(lái)源:北京市石景山區(qū)2010屆高三下學(xué)期統(tǒng)一測(cè)試一 題型:閱讀理解


D
Film cameras and digital cameras work in a similar way.
Film cameras
After all, a film camera is basically a light – proof (不透光的) box. It has a lens (鏡頭) system to focus light onto the film at the back of the camera.
Let’s suppose that we are outside on a beautiful summer day trying to take a picture of the family dog. We are using a film camera. We finally get the dog to lie still. You point the camera at him. What happens? Light goes into the camera lens and hits the shutter. In other words, nothing happens yet. Now let’s say that the dog looks really cute and you decide to snap a picture. What happens? When you press the button, the shutter open for a very short period of time. A small amount of light passes through and hits the film at the back of the camera. This creates an upside-down and reversed (反向的)image on the film.
When you finish the roll of the film, you can take it to the photo shop to develop it and you will have a great picture of your dog!
Cameras come with different lens lengths. Why does it matter? Many small cameras have shorter focal lengths, which means that there is a small distance between the lens and the place where the light focuses at the back of the camera. This gives you a large view of the area you are taking a picture of. Lenses with a long focal length show a smaller area but allow you to focus on distant objects and make them bigger. They are often called telephoto lenses. A good example of a long focus lens is one that is used by sports photographers to get photos of football players as if they were standing right beside them.
Digital cameras
In digital cameras, the light falls not on film but onto a sensor (傳感器)called a CCD (Charge Coupled Device). This digitally converts(轉(zhuǎn)變) light and colour into a digital information or pixels (象素). The CCD is the heart of any digital camera and usually the most expensive part ---- depending on how good it is.
67.Which of the following statements is TRUE?
A.Both digital and film cameras focus light onto the film.
B.All cameras have a sensor.
C.Digital cameras and film cameras have something in common. .
D.Small cameras usually have longer focal lengths.
68.In the “Film cameras” part, you fail to take the picture of the dog because _____.
A.light goes into the camera lens and hits the shutter
B.you haven’t aimed the camera at the dog
C.the image of the dog is not created
D.the sensor fails to convert light and colour into a digital information
69.The main reason that sports photographers can get clear and big photos of players is that _ ___.
A.they use digital cameras  B.the lens of their cameras is excellent
C.their focus lenses are short      D.their focus lenses are long
70.Generally speaking, a digital camera’s price is ____.
A.closely related to the quality of the CCD
B.irrelevant to the quality of the CCD
C.closely related to the lens
D.irrelevant to the lens

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