In most situations, light helps us see. But when it comes to looking at the night sky, light is actually a kind of pollution. It prevents our view of some of life’s most striking sights: stars, planets, and even galaxies.
“When I was a little boy, I loved the night sky. I remember looking up and the sky was filled with stars. I became an astronomer because I was amazed by their beauty,” says Robert gent, “Now in most big cities kids can’t see the stars like I did.”
Normally, about 2,500 individual stars are visible to the naked eye without using any special equipment. But because of light pollution, you actually see just 200 to 300 and fewer than a dozen from some cities. Only one in three Americans can see our own galaxy (星系) with the naked eye. Those people live far away from the lights of big cities, office building, and shopping malls.
Fortunately, there’s an inexpensive and useful way. If we shine lights down at the ground instead of up into the sky, and use lower brightness levels, we can save big amounts of energy and keep the beauty of the night skies. Many cities and towns have passed laws limiting lights at night, making sure enough shine for safety without creating much light pollution.
Light pollution affects more than our view of the heavens and can harm wildlife. Migrating (迁移) birds sometimes fly over cities and become confused by the brightness, flying in circles until they drop from exhaustion. Sea turtles need dark beaches for nesting and won’t approach bright lights. Too much light at night may even affect human health. For all these reasons, researchers are working on ways to use light only when and where they are truly needed. Everyone deserves to look up at the sky.
【小题1】According to the text, using our naked eyes, ______________.

　In a great many cities, hundreds of people ride bicycles to work everyday. In New City, some bike riders have even formed a group called Bike for a Better City. They declare that if more people rode bicycles to work, there would be fewer automobiles(汽车) in the downtown part of the city and so less dirty air from car engines. For several years this group has been trying to get the city government to help bicycle riders. For example. They want the city to draw special lanes(通道) for bicycles only on some of the main streets, because when bicycle riders must use the same lanes as cars, there are accidents. Bike for a Better city feels that if there were special lanes more people would use bikes.
But no bicycles lanes have been drawn. Not everyone thinks they are a good idea-----they say it will slow traffic. Some store owners on the main streets don't like the idea------they say that if there is less traffic, they will have less business.
The city government has not yet decided what to do. It wants to keep everyone happy. On weekends, Central Park----the largest place of open ground in New York----is closed to cars, and the roads may be used by bicycles only. But Bike for a Better City says that this is not enough and keeps fighting to get bicycle lanes downtown.
73. The bike riders suggest that _____________.
A. bicycles should be used instead of cars    B. bicycle lanes should be drawn
C. fewer buses or cars should be used  D. the number of special lanes should be increased
74. The advantage(好处) of the special lanes is that _______.
A. they will make cars and buses run slowly   B. they will make it easier for bike riders to go to parks
C .they will make the city more beautiful    D. the lanes will prevent accidents
75. The government has not decided whether special lanes should be drawn ______.
A. so that everyone is disappointed      B. because there are different opinions
C. because most people travel by train   D. because Bike for a Better City is not strong enough

A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.
Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.
Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳动物) have unexpectedly been discovered in the skin of mice.
“No one had ever looked,” explained Randall Johnson, a biologist researcher.
Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.
“We have no reason to think that they are not in the skin of people too,” Johnson said.   These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen—a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.
These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a multibillion-dollar market, Johnson said.
Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however—there’s a lot we don’t know yet,” Johnson explained.
The scientists detailed their findings in the April 18 issue of the journal Cell.
49. Which of the following statements is TRUE according to the passage?
A. Johnson believes that Oxygen sensors also exist in human skin.
B. People have to surf the Internet to read detailed findings.
C. It has been proved that these findings help treat lung diseases.
D. It has long been expected oxygen sensors exist in mice’s skin. 
50. One of the functions of the molecules mentioned above is _______.
A. carrying oxygen around the body                   B. improving athletes’ performance
C. detecting oxygen                                          D. increasing level of oxygen
51. What is Johnson’s attitude to the application of the findings to the athletes’ training?
A. Negative                  B. Doubting                  C. Positive             D. Hesitating
52. The best title of the passage may be _______.
A. Great Findings Benefits Athletes A Lot
B. Frogs And Mice Are Distant Relatives
C. First Known Animal Breathes Through Skin
D. Humans Might Sense Oxygen Through Skin

The Peppered Moth, a kind of insect, is found in England. It is light brown in color and likes to settle on trees which are also light brown. This makes the moth difficult to be seen and birds are less likely to notice and eat it.
But with the development of industry, smoke from factories began to reach the trees where the moth settled. It made the trees blacker. Then something very strange took place: in industrial areas, the Peppered Moth began to change color. It became darker as well. Although the change took several years, some scientists soon noticed that newly-born moths were a little darker than usual.
A scientist called Kettle Well decided to make a careful study of this. He marked some of the light moths and some of the darker ones, and set them free in the woods near Birmingham, an industrial city. Later he retarget as many the marked moths as possible ( The result was given in the chart ).
Kettle Well’s research was done in the early 1950s. Soon afterwards Britain introduced new laws to reduce smoke and factory pollution.
Can you imagine what would happen to the Peppered Moth as the air became cleaner again? 

  When scientists set out to explore the roots of human laughter, some apes（类人猿） were just tickled（胳肢）to help. That’s how researchers made a variety of apes and some human babies laugh. After analyzing the sounds, they concluded that people and great apes inherited laughter from a shared ancestor that lived more than 10 million years ago. Experts praised the work, it gives strong evidence that ape laughter and human laughter are related through evolution（进化）.
Scientists have noted that apes make characteristic sounds during play or while being tickled, especially to signal that they’re interested in playing. It’s been suggested before that human laughter grew out of primate（灵长类动物） roots. But ape laughter doesn’t sound like human laughter. It may be slower noisy breathing. So what does that have to do with the human ha-ha? To investigate that, Marina Davila Ross and her colleagues carried out a detailed analysis of the sounds made by tickling three human babies and 21 other primates, apes included.
After measuring 11 features in the sound from each species, they tried to find out how these sounds appeared to be related to each other. The result looked like a family tree. Significantly, that tree matched the way the species themselves are related, the scientists reported online in the journal Current Biology. They also concluded that while human laughter sounds much different from ape laughter, their typical features could have come from the same ancestor.
Panksepp, who studies laughter-like responses in animals but didn’t participate in the new work, called the paper exciting. Panksepp’s own work concludes that even rats produce laughter in response to playing and tickling, with sounds that can hardly be heard by people. Robert Provine, a scientist, who wrote the book, Laughter: A Scientific Investigation, said the new paper showed some important clues, like ape sounds that hadn’t been realized before.
69. Why did the scientists analyze the laughter made by tickling human babies and apes?
A. To try to discover if they can make characteristic sounds.
B. To see if they interested in playing.
C. To find out if the laughter of apes and humans is related.
D. To find out the differences between humans and apes.
70. Based on Paragraph 3 we can know that researchers measured the features in the sound to ________.
A. find out ape sounds that hadn’t been realized before
B. find out relations among primates’ laughter
C. see what a family tree from each species looks like
D. make a report online in the journal Current Biology
71. What can be inferred from the last paragraph?
A. Panksepp spoke highly of the new research.
B. Rat laughter is likely to be related to ape laughter.
C. Robert Provine provided some new clues for the researchers.
D. Humans don’t enjoy listening to ape laughter.
72. What would be the best title for the passage?
A. Ape study explores evolution of laughter.
B. Apes like to laugh when being tickled.
C. Human laughter and ape laughter are different.
D. Laughter: A Scientific Investigation.

The invention of the electric telegraph gave birth to the communications industry. Although Samuel B. Morse succeeded in making the invention useful in 1837, it was not until 1843 that the first important telegraph line was constructed. By 1860 more than 50,000 miles of lines connected people east of the Rockies. The following year, San Francisco was added to the network.
The national telegraph network strengthened the ties between East and West and contributed to the rapid expansion of the railroads by providing an efficient means to monitor schedules and routes. Furthermore, the extension of the telegraph, combined with the invention of the steam-driven rotary printing press by Richard
M. Hoe in 1846, revolutionized the world of journalism. Where the business of news gathering had been dependent upon the mail and on hand-operated presses, the telegraph expanded the amount of information a newspaper could supply and allowed for more timely reporting. The creating of the Associated Press as a central wire service in 1846 marked the arrival of a new era (纪元) in journalism.
71. The main topic of the passage is        .
A. the history of journalism                                B. the origin of the national telegraph
C. how the telegraph network contributed to the expansion of railroads
D. the contributions and development of the telegraph network
72. The word "gathering" in line 11 refers to        .
A. people                    B. information                   
C. objects                                     D. substances
73. The author's main purpose in this passage is to         .
A. compare the invention of the telegraph with the invention of the steam-driven rotary press
B. propose new ways to develop the communications industry
C. show how the electric telegraph affected the communications industry
D. criticize Samuel B. Morse
74. This passage would most likely be found in a        .
A. U.S. history book   B. book on trains  
C. science textbook D. computer magazine
75. It can be inferred from the passage that          .
A. Samuel Morse did not make a significant contribution to the communications industry
B. Morse's invention did not immediately achieve its full potential (潜力)
C. the extension of the telegraph was more important than its invention
D. journalists have the Associated Press to thank for the birth of the communications industry

CHINA
Coal mines claim (使…失踪) more lives
A COAL mine blast (爆炸) in Jixi, Helongjiang, left more than 100 miners dead on Thursday .Ten mines in Jixi were ordered to stop production. The government has tried to shut down thousands of small, illegal (非法的)  mines in the country that do not meet safety standards(标准).
MIDDLE EAST 
Bombers continues to kill
PALESTINIANS killed 32 Israelis in three major attac between Tuesday and Thursday. There were two suicide bombing (自杀性爆炸) and a militant (武装的) attack on Jewish settlement. They led to one of the highest Israeli death tolls ( 死亡人数)  in such a short period over the last two years.
CHINA
Young people stand tall
The average height of Chinese young people has risen by 6 centimeters pared to that of 20 years ago. This year far exceeds (超过)  the word’s average growth speed. A survey on health conducted by a panel(调研组) of Chinese students found the results. According to the world average level, youths get taller by 1 cm every 10 years.
CANADA
Talking about world issue (援助)
The Group of Eight (G8)—the US, Japan , Germany, Britain, France, Italy , Canada and Russia ---- will hold a summit(峰会)on June26 and 27 in Kananaskis, Canada. The G8 are the richest and most powerful countries in the world. G8 leaders and some African presidents will discuss strengthening global economic growth and helping Africa. Kofi Annan, United Nations Secretary General, will also attend.
1. Thousands of mines have been shut because ______.
A. they have blast                     B. they produced less coal  
C. they are very small and illegal         D. they don’t meet the safety standards
2. In the last 20 years, the average growth speed of Chinese youths exceeds the world’s average level by _______.
A.1 cm                     B.4 cm             C. 5 cm      D. 6 cm
3. What’s the purpose of the Summit ? 
A. to strengthen the global economic growth and helping some poor African countries.
B. To make these eight countries much more powerful.
C. To help some African president to strengthen their economic growth.
D. Kofi Annan will have an important speech on world issues.

E
After a busy day of work and play, the body needs to rest. Sleep is necessary for good health. During this time, the body recovers from the activities of the day. The rest that you get while sleeping makes it possible for your body to prepare itself for the next day.
There are four levels of sleep, each being a little deeper than the one before. As you sleep, your body relaxes little by little. Your heart beats more slowly, and your brain slows down. After you reach the fourth level, your body shifts(变换) back and forth from one level to the other.
Although your mind slows down, you will dream from time to time. Scientists who study sleep point out that when dreaming occurs, your eyeballs begin to move more quickly (although your eyelids are closed). This stage of sleep is called REM, which stands for rapid eye movement.
If you have trouble falling asleep, some people recommend(建议) breathing very slowly and very deeply. Other people believe that drinking warm milk will make you drowsy. There is also an old suggestion that counting sheep will put you to sleep.
49. During REM, ______
A. you move restless                                         B. you start dreaming
C. your mind stops working                                         D. your eyeballs move quickly
50. A good title for this text might be_________
A. Dreams                     B. Sleep                C. Good Health      D. Work and Rest

Space is a dangerous place, not only because of meteors (流星 ) but also because of rays from the sun and other stars. The atmosphere again acts as our protective blanket on earth. Light gets through, and this is essential for plants to make the food which we eat. Heat, too, makes our environment endurable（可忍受的）. Various kinds of rays come through the air from outer space, but enormous quantities of radiation（辐射） from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space. The unit of radiation is called "rem". Scientists have reason to think that a man can put up with far more radiation than 0.1 rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage - a person may feel perfectly well, but the cells of his or her sex organs may be damaged, and this will no be discovered until the birth of abnormal children or even grandchildren.
Missions of the Apollo flights have had to cross belts of high amount of rems. So far, no dangerous amounts of radiation have been reported, but the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones have been found so far.
1. According to the first paragraph, the atmosphere is essential to man in that ____.
A. it protects him against the harmful rays from space
B. it provides sufficient light for plant growth
C. it supplies the heat necessary for human survival
D. it screens off the falling meteors
2. We know from the passage that ____.
A. exposure to even tiny amounts of radiation is deadly
B. the effect of exposure to radiation is slow in coming
C. radiation is avoidable in space exploration
D. astronauts in spacesuits needn't worry about radiation damage
3. The harm radiation has done to the Apollo crew members ____
A. is significant            B. seems overestimated
C. is enormous             D. remains unknown
4. It can be inferred from the passage that ____.
A. the Apollo mission was very successful
B. protection from space radiation is no easy job
C. astronauts will have deformed children or grandchildren
D. radiation is not a threat to well-protected space explorers
45. The best title for this passage would be ____.
A. The Atmosphere and Our Environment   B. Research on Radiation
C. Effects of Space Radiation             D. Importance of Protection Against Radiation

The following conversation is between Susan Russell-Robinson from the US Geological （地质学的）Survey and Barbara Reynolds from USA Today .
Q: Why , after 600 years of no activity , did Mount Pinatubo in Philippines erupt（喷发）in 1991 ?
A: Volcanoes （火山）each have their own eruption styles . This volcano probably has a rule which makes it erupt in the order of every 500 to 1000 years , but a volcano in Hawaii seems to erupt every year , and some of the Alaskan volcanoes might erupt every 10 or 20 years .
Q: So nothing caused it ?
A: There’s nothing out of the ordinary . If you were to take an ordinary calendar year , 50 to 75 or 80 volcanoes erupt around the world every year . There are 20 to 30 volcanoes every month that show signs of unrest . That might be a full-blown eruption or a whole host of activities like that .
Q: What is “the ring of fire” ?
A: If you look at where active volcanoes are placed around the world , there are somewhere between 500 and 600 of them . There is what appears to be almost a necklace that goes around the Pacific Ocean . It makes a ring where 60% of the world’s volcanoes lie .
Q: Why such a concentration（集中）there ?
A: That’s based on a theory that the oceans and the continents are like separate pieces . When they move , one might ride up over the other one . In this case , the Pacific Ocean goes under the continents and when that happens it seems to produce magma （熔岩）at depth and then you have volcanoes in the same ring .
1．What kind of writing do you think this passage is ?
A．A text taken from a geography book .    B．An interview published in the press .
C．A conversation carried out in a film .     D．An oral test recorded as an example .
2．Which of the following statements can correctly explain why we have so many volcanoes around the Pacific Ocean ?
A．The movement of the surface of the earth makes it possible.
B．The Pacific Ocean produces magma and presses it everywhere.
C．The oceans and the continents are separated from each other.
D．The earth’s surface around the Pacific is thinner than any other part.
3．Barbara Reynolds’ main purpose here is______________ .
A．to show how dangerous volcanoes are to the world
B．to learn what signs a volcano gives us before its eruption
C．to warn the world of the existence of “the ring of fire”
D．to introduce some general idea of volcanoes to the public
4．Which of the following can be considered as the best conclusion of the conversation?
A．There are so many volcanoes in the world and we are always in danger.
B．Volcanoes have erupted more frequently than ever before.
C．Volcanoes are waiting to be better known.
D．Something must be done to protect the people near the ring of fire.