A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
Because no light can get out, people can’t see black holes. Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently from other ones.
Black holes can be big or small. Scientists think the smallest black holes are as small as just one atom. These black holes are very tiny but have the mass of a large mountain. Mass is the amount of matter, or “staff”, in an object.
Another kind of black hole is called “stellar”(星球黑洞). Its mass can be up to 20 times more than the mass of the sun. There may be many stellar mass black holes in Earth’s galaxy. Earth’s galaxy is called the Milky Way.
The largest black holes are called “supermassive”(超大质量黑洞). These black holes have masses that are more than one million suns together. Scientists have found proof that every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy has a mass equal to about four million suns and would fit inside a very large ball that could hold a few million Earths.
Scientists think the smallest black holes formed when the universe began. Stellar black holes are made when the center of a very big star falls in upon itself, or falls apart. When this happens, it exploded part of the star into space. Scientists think supermassive black holes were made at the same time as the galaxy they are in.
A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole. But scientists can see how the strong gravity affects the stars and gas around the black hole. Scientists can study stars to find out if they are flying around, or orbiting a black hole.
When a black hole and a star are close together, high-energy light is made. This kind of light cannot be seen with human eyes. Scientists use satellites and telescopes in space to see the high-energy light.
【小题1】The gravity of a black hole may become so strong that light cannot get out when ____________.
| A．the star is going to die |
| B．special tools are used on it |
| C．other stars come close to it |
| D．it is seen from the space telescopes |
| A．A black hole can be very tiny but extremely heavy. |
| B．The gravity of a black hole holds all light in its center. |
| C．Scientists observe high-energy light through their own eyes. |
| D．Some small black holes came into being as early as the universe. |
| A．a black hole | B．the Milky Way |
| C．a series of stars | D．a planet near the earth |
| A．Neither the sun nor the earth is as heavy as a black hole. |
| B．There is a supermassive black hole at the center of the Milky Way. |
| C．The supermassive black hole had existed before the Milky Way was formed. |
| D．There is a reason why the large black holes are called “supermassive”. |
| A．what a black hole is |
| B．how black holes form |
| C．how big black holes are |
| D．how scientists know about black holes |
【小题1】A
【小题2】C
【小题3】C
【小题4】D
【小题5】D
解析试题分析：文章介绍黑洞的形成，它的特点以及科学家探索研究黑洞的方法。
【小题1】细节题：根据文章第一段中“This can happen when a star is dying.”可知恒星的死亡可能会形成黑洞。故选A。
【小题2】细节题：根据第三段中“These black holes are very tiny but have the mass of a large mountain”这些黑洞可能会非常小，但是有一座山一样的质量，可知A正确；根据倒数第二段中“A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole.”黑洞不可见是因为强大的引力将所有的光线吸进黑洞的中间，可知B项正确；根据最后一句“Scientists use satellites and telescopes in space to see the high-energy light.”科学家们使用卫星和太空望远镜查看高能光，可知科学家不是用自己的眼睛，因此C错误；根据第六段中“Scientists think the smallest black holes formed when the universe began.”科学家认为最小的黑洞在宇宙开始时形成，可知D项正确。故选C。
【小题3】推理题：根据第四段中“Earth’s galaxy is called the Milky Way”地球所在的星系叫银河系，常理可知星系是有很多星星组成的。故选C。
【小题4】推理题：根据第五段最后一句“The supermassive black hole at the center of the Milky Way galaxy has a mass equal to about four million suns and would fit inside a very large ball that could hold a few million Earths.”在银河系中心的超大质量黑洞的质量相当于四百万个太阳,是一个可以容纳几百万地球在内的巨大的球，由此可知这是在解释什么叫做“超大质量黑洞”。故选D。
【小题5】推理题：阅读最后两段内容可知是在介绍科学家是如何找到黑洞的。故选D。
考点：考查科普教育类阅读
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小学生10分钟应用题系列答案科目：高中英语 来源： 题型：阅读理解
October 15th is the Global Handwashing Day. Activities are planned in more than 20 countries to get millions of people in the developing world to wash their hands with soap. For example, donors（捐赠者） will give 150,000 bars of soap to schools in Ethiopia.
Experts say people around the world wash their hands every day, but very few use soap at so-called important moments. These include after using the toilet, after cleaning a baby and before touching food.
Global Handwashing Day is the idea of the Public-Private Partnership for Handwashing with Soap. Partners include the United Nations Children’s Fund, American government agencies, the World Bank and soap makers Unlever and Procter and Gamble. The organizers say all soaps are equally effective at removing disease-causing germ(细菌). They say the correct way to wash is to wet your hands with a small amount of water and cover them with soap. Rub（揉搓） it into all areas, including under the fingernails（指甲）. Rub for at least twenty seconds. Then rinse well under running water. Finally, dry your hands with a clean cloth or wave them in the air.
The Partnership for Handwashing says soap is important because it increases the time that people spend in washing hands. Soap also helps to break up the dirt that holds most of the germs. And it usually leaves a pleasant smell. The Partnership for Handwashing also says washing with soap before eating or after using the toilet could save more lives than any vaccine(疫苗)or medicine. Hand washing could also prevent the spread of other diseases. When people get germs on their hands, they can infect（感染）themselves by touching their eyes, noses or mouths. Then they can infect others.
【小题1】What’s the best title for this passage?
| A．Say no to washing hands in the wrong way. |
| B．Find out why washing hands carefully is so important. |
| C．Hand washing: so important----it gets a day of its own. |
| D．Want to live a longer life?-wash your hands. |
| A．to dry your hands | B．to wash away the soap |
| C．to rub your hands carefully | D．to clean your fingers |
| A．how to wash your hands correctly |
| B．why washing hand with soap is so important |
| C．the dangers of washing hands without soap |
| D．when we should especially wash our hands with soap |
| A．Medical care | B．Public service | C．Health report | D．Advertisement |
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科目：高中英语 来源： 题型：阅读理解
Mulch is a protective cover of material that is spread on top of soil.It is usually made out of organic material, like crop waste.Farmers may keep the remains of maize or other crops on top of the soil.This creates mulch on the soil surface.The plant remains help protect the soil against wind and water damage.Mulching is one of the best things people can do for their plants.It also helps keep the soil from getting dry, and reduces the need for watering plants.It also limits temperature changes in the soil.And it stops unwanted plants, or weeds，from growing.
Organic mulch improves the condition of soil.As the mulch breaks down, it provides material which keeps the soil from getting hard.This improves the growth of roots and increases the movement of water through the soil.It also improves the ability of the soil to hold water. Organic mulch contains nutrients for plants.It also provides a good environment for earthworms and other helpful organisms in the soil.
It is easy to find organic mulch materials.Cutup leaves and small pieces of tree bark can be used.Grass cuttings are also a good mulch for plants. Mulch from newspapers works well in controlling weeds.
The best time to add mulch depends on your goal.Mulch provides a thick barrier between the soil and the air.This helps to reduce temperature changes in the soil. As a result，mulched soil will be cooler than other soil in the summer.In winter, the mulched soil may not freeze as deeply as other soil.The best time is after the ground has frozen, but before the coldest weather arrives.Spreading mulch before the ground has frozen may attract small animals searching for a warm place to spend the winter.Delaying the spreading should prevent this problem.The animals will probably find another place to live.
【小题1】The author tells us the following EXCEPT________.
| A．what mulch is and its benefits |
| B．the best time to add mulch |
| C．what can be mulched on the soil surface |
| D．the bad effects of mulch |
| A．tree barks | B．cutup leaves |
| C．grass cuttings | D．plastic |
| A．Protecting the soil against wind and water damage. |
| B．Keeping the soil wet and reducing the need for watering plants. |
| C．Reducing temperature changes in the soil and stopping unwanted weeds growing. |
| D．All of the above. |
| A．improve the condition of soil |
| B．improve the ability of the soil to hold water |
| C．provide a good environment for earthworms |
| D．improve the growth of roots and increase the movement of water through the |
| A．the best time to add mulch is in spring and summer |
| B．the best time to add mulch is after the coldest weather arrives |
| C．the best time to add mulch depends on weather |
| D．choosing the best time to add mulch can avoid attracting small animals |
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科目：高中英语 来源： 题型：阅读理解
BEIJING - By the end of 2011 China-made supercomputers will say goodbye to foreign microchips（微芯片） and start using their own "Chinese core(核心)", according to one of the country's leading scientists, Hu Weiwu.
Hu told reporters on Saturday that the "Dawning 6000" supercomputer, developed by the Institute of Computing Technology of CAS and the Dawning Information Industry Company (DIIC), will adopt Loongson microchips for the first time as its core parts. It will have a computing speed of more than 1,000 trillion operations a second.
Making supercomputers with Chinese microchips is one of the nation's major science and technology projects. Three organizations - the Institute of Computing Technology of CAS, Jiangnan Institute of Computing Technology and the National University of Defense Technology (NUDT) - have their own supercomputer projects.
According to their schedules, all three institutions will need to meet the target of using domestically（国内的） developed microchips by the end of this year. Hu said the new supercomputer will use fewer than 10,000 Loongson microchips, and will also be more energy-efficient.
Tianhe-1A, developed by NUDT in Hunan's provincial capital Changsha, is the fastest supercomputer in the world. However, Tianhe-1A largely runs on 14,336 CPUs made by Intel, and 7,186 GPUs (processing units) from Nvidia, two US chip-makers.
Hu said there will be difficulties ahead as there is little affiliated equipment specially developed for these supercomputers. "We have enough supercomputers in China but still can't make full use of them," He said.
Hu added that although the China-made CPUs have improved since they were first produced in 2002, they have a long way to go to compete with US chip-makers such as Intel.
【小题1】What’s the best title for this passage?
| A．The Arrival of Chinese Supercomputers |
| B．Homemade CPUs with a Long Way to Go |
| C．The Supercomputers of Three Organizations in China |
| D．Homemade CPUs on the Way for Local Supercomputers |
| A．Dawning 6000 | B．Loongson microchips |
| C．DIIC | D．Tianhe-1A |
| A．cheap | B．suitable | C．expensive | D．modern |
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科目：高中英语 来源： 题型：阅读理解
In the second half of each year, many powerful storms are born in the tropical Atlantic and Caribbean seas. Of these, only about a half a dozen generate the strong, circling winds of 75 miles per hour or more that give them hurricane status, and several usually make their way to the coast. There they cause millions of dollars of damage, and bring death to large numbers of people.
The great storms that hit the coast start as innocent circling disturbances (气旋) hundreds — even thousands — of miles out to sea. As they travel aimlessly over water warmed by the summer sun, they are carried westward by the trade winds. When conditions are just right, warm, moist (潮湿的) air flows in at the bottom of such a disturbance, moves upward through it and comes out at the top. In the process, the moisture in this warm air produces rain, and with it the heat that is switched to energy in the form of strong winds. As the heat increases, the young hurricane begins to turn around in a counter-clockwise motion (反时针方向).
The average life of a hurricane is only about nine days, but it contains almost more power than we can imagine. The energy in the heat released (释放) by a hurricane’s rainfall in a single day would satisfy the entire electrical needs of the United States for more than six months.
Water, rather than wind, is the main source of death and destroying in a hurricane. A typical hurricane brings 6-to-12-inch downpours resulting in sudden floods. Worst of all is the powerful movement of the sea — the mountains of water moving toward the low-pressure hurricane center. The water level rises as much as 15 feet above normal as it moves toward shore.
【小题1】An ordinary tropical storm is called a hurricane when ______.
| A．it occurs in the Caribbean seas |
| B．its winds reach 75 miles per hour |
| C．it makes its way to the coastline |
| D．its winds begin to circle on the sea |
| A．The rough water. | B．The violent winds. |
| C．The heat it gives out. | D．The length of its life. |
| A．The hurricane is extraordinarily powerful. |
| B．The hurricane is used to generate electricity. |
| C．The hurricane can otherwise offer an unusual sight. |
| D．The hurricane can give people an unforgettable experience. |
| A．the low-pressure area in the center of the storm |
| B．the force of waves of water |
| C．the increasing heat |
| D．the trade winds |
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科目：高中英语 来源： 题型：阅读理解
You don't need to get in a time-traveling machine to see how technology will reshape our lives, such as the way we shop．Several new technologies that are to change your buying habits already exist．Let's see what's in store for your future shopping．
Try it on, virtually （虚拟的）．Want to shop online for a new pair of eyeglasses? You don't need to guess which pair looks best on you. Go and see the eBay Fashion iPhone app to try a pair of eyewear you're checking out on a picture of your face．But what if you want to buy something bigger? Thanks to Microsoft Kinect's motion tracking camera, you can cover clothes on your screen body．You can even choose the background of your virtual fitting room to enrich your shopping experience．
Get a perfect, custom fit．Everyone's body is shaped differently．To get a perfect fit, you sometimes have to get your clothes changed．But by using 3D scanning technology, all the clothes you buy will fit your body perfectly．Some companies scan your body using High-tech to get the most accurate measurements, so they can make special clothes just for you．
High-tech shopping carts and checkout counters．High-tech shopping carts could, in time, be a common sight in malls and supermarkets．Microsoft Kinect-enabled carts are currently under test．The cart can follow you along the aisles （通道）, controlled merely by your movement and your voice．In China, a supermarket chain introduced tablet-equipped carts that guide shoppers around the stores' aisles．
In the United States, several supermarkets use a device called Scan It that gives buyers the freedom to scan purchases on their own while they shop．While it's great not having to line up at a checkout counter, we wouldn't mind it if the store used Toshiba's new Object Recognition Scanner．The machine identifies a product as soon as it's placed in front of a camera just by its shape and color, even if it has no bar code．
【小题1】What's the best title for this text?
| A．Ways for future shopping |
| B．Influence of new technology |
| C．Inventions to change habits |
| D．A new time-traveling machine |
| A．make vivid pictures of our face |
| B．help us sell more clothes online |
| C．create us a virtual dressing room |
| D．choose suitable eyeglasses for us |
| A．Object Recognition Scanner． |
| B．The eBay Fashion iPhone app． |
| C．3D scanning technology． |
| D．Microsoft Kinect-enabled carts． |
| A．the customer's voice |
| B．its shape and color |
| C．the customer's movement |
| D．the bar code on it |
| A．Checkout counters will disappear from supermarkets in future． |
| B．Buyers can use Scan It to go around the supermarket by themselves． |
| C．High-tech shopping carts will be widely used in malls and supermarkets． |
| D．The new technologies are only dreams that are impossible to come true． |
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科目：高中英语 来源： 题型：阅读理解
Bottled water has become the choice for people who are healthy and thirsty. Bottled water is all over the world. But some say the planet’s health, and people’s health may be suffering from it.
The idea that bottled water is safer for humans may not be true. The Natural Resources Defense Council of America said, “There is no promise that because water comes out of a bottle, it is cleaner or safer than water from the tap.” Another New York City-based action group added that some bottled water is “really just tap water in a bottle—sometimes more clean, sometimes not.”
It is not proven that bottled water is better than tap water. Nick Reeves from the Chartered Institution of Water and Environmental Management said, “The high mineral content (含量) of some bottled water makes them not good for feeding babies and young children.” Also, most bottled water doesn’t have fluoride (氟化物), which can make teeth stronger. Kids are drinking more bottled water and less fluoridated tap water, and some say that’s behind the recent rise in bad teeth.
Storing is another problem. Placed near heat, the plastic bottles can produce bad chemicals (化学物质) into the water.
According to the Environmental Protection Agency, some 2.7 million tons of plastic are used worldwide to bottle water each year. The plastic can take between 400 and 1,000 years to break down.
In terms of energy use, plastic bottles are also not cheap. One report said that if water and soft drink bottlers had used 10 percent recycled materials in their plastic bottles, they would have saved about 72 million gallons of gas.
So, if you are worried about the effect of bottled water on the Earth, you can take the following steps.
● Drink from your tap. Unless your government warns against this, it should be fine.
● Get a container (容器). Carry your tap water in a steel or a lined drinking container, and clean it between uses.
● Keep it cool. Don’t drink from a bottle that has been sitting in the sun, don’t store it near chemicals, and don’t reuse plastic bottles.
● Choose glass containers over plastic if possible. When finished, recycle!
【小题1】What is the main idea of the article?
| A．Drinking tap water is the only choice for people. |
| B．Glass containers are better than plastic bottles. |
| C．Plastic bottles are harmful to the environment. |
| D．Bottled water may not be as good as we think. |
| A．They break down in less than 300 years. | B．They can be used for many other things. |
| C．They are a risk to the environment. | D．They are cheap to make. |
| A．no problem for the environment | B．more expensive than tap water |
| C．always safer than tap water | D．better for babies |
| A．There are a lot of problems storing tap water. |
| B．Bottled water can be just tap water in a bottle. |
| C．It may be better for your teeth. |
| D．It may contain fluoride. |
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科目：高中英语 来源： 题型：阅读理解
What if I took that big jump on my bike?What’s the worst thing that could happen if I go out at midnight?Should try smoking?The teen years can play out like a choose-your-own-adventure novel.
Teenagers must act on an endless parade of choices.Some choices.including smoking.Come with serious consequences.As a result, adolescents often find themselves trapped between their impulsive tendencies（-Just try it!)and their newfound ability to make well-informed and logical choices（-Wait, maybe that’s not such a good idea!）.
So what makes the teenager’s brain so complex? What drives adolescents-more than any other age group-to sometimes make rash or questionable decisions?
If you have ever thought that the choices teenagers make are all about exploring and pushing limits, you are on to something. Experts Experts believe that this tendency marks a necessary period in teen development.The process helps prepare teenagers to confront the world on their own. It is something all humans have evolved to experience-yes, teens everywhere go through this exploratory period.Nor is it unique to people:Even laboratory mice experience a similar stage during their development.
For example，laboratory experiments show that young mice stay close by their mothers for safety. As mice grow．their behavior does too．“When they reach puberty，they’re like，‘I’m gonna start checking out how this environment looks without my mom，…explains Beatriz Luna,of the University of Pittsburgh．
As a developmental cognitive neuroscientist，Luna studies those changes that occur in the brain as children develop into adults．She and other researchers are showing how the teen experience can lead to powerful advantages later in life．Take mice again：Young mice that explore most tend to live longest——that is，unless a cat eats them，Luna adds．
【小题1】What is the best title for the text?
| A．Teenagers make endless choices |
| B．The teenage brain drives them to be different |
| C．How the teenage brain develops |
| D．Researches about the teenagers |
| A．It means “you are wrong”. |
| B．It means“you lose your way”． |
| C．It means“you get the point”． |
| D．It means“you are off the point”. |
| A．make no mistakes in his life． |
| B．have advantages over others. |
| C．loSe his confidence even his life. |
| D．experience no failure and live Iongest. |
| A．young mice try to look for safety. |
| B．Young mice like to stay with their mothers. |
| C．Mice also experience a period to explore the world. |
| D．Mice experience different stages. |
| A．How call a teenager make right choices |
| B．Why the parents shouldn’t allow teenagers to smoke |
| C．What has been discovered in the lab experiment． |
| D．What really goes on in the teenage brain. |
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科目：高中英语 来源： 题型：阅读理解
Surfing the Internet for fun will make you a better employee,according to an Australian study.
The University of Melbourne study shows that people who use the Internet for their own reasons at work are about 9 percent more productive than those who do not. Study author brent Coker said“Surfing the Internet at times helps increase an employee’s attention.”
“People need to relax for a bit to get back their attention,”Coker said on the university’s website.”Having a short break, such as a quick surfing of the Internet, helps the mind to rest itself,leading to a higher total Internet attention for a day’s work, and as a result, increase productivity(生产效率),”he said.
According to the study of 300 workers ,70 percent of people who use the Internet at work surf the Internet for their own reasons during office hours. Among the most popular surfing activities are searching for information about products, reading online news, playing online games and watching videos.”Firms spend a lot of money on software to block their employees from watching video, using social networking sites or shopping online, ”said Coker.”that’s not always a good idea.”
However, Coker said the study looked at people who surfed the Internet in moderation(),or were on the Internet for lee than 20 percent of their total time in the office.”Those who spend too much time surfing the Internet will have a lower productivity than those without,”he said.
【小题1】What does the University of Melbourne study mainly show?
| A．People who surf the Internet are good employees. |
| B．Not everyone surfs the Internet for fun during office hours. |
| C．Surfing the Internet for fun during office hours increase productivity. |
| D．The Internet is becoming more and more important in people’s life. |
| A．the longer a person’s mind rests the better attention he will have. |
| B．surfing the Internet is the best way to increase productivity. |
| C．workers should have a long break during office hours |
| D．workers should let their minds rest now and then. |
| A．Watching videos. | B．reading online news. |
| C．Reading online novels. | D．Playing online games. |
| A．prevent | B．cycle | C．burst | D．breathe |
| A．Spending too much time surfing the Internet reduces productivity. |
| B．Those who never surf the Internet have the lowest productivity. |
| C．Most people don’t surf the internet in modernation during office hours. |
| D．People should spend as little time as possible surfing the Internet. |
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