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If you look at the night sky, you’ll often see stars moving very quickly. In fact, they move much more quickly than they should according to their size and the laws of physics.
Scientists do not completely understand why the speed of these stars is so high. But many believe the reason is that much of the universe is made of something called “dark matter”. Groups of stars called galaxies, such as the Milky Way, might even be made up of 90 percent dark matter.
How much something weighs depends on where it is. The same object weighs only half as much on Mars as it does on Earth and almost three times as much on Jupiter. So scientists prefer to talk about the mass (质量) of something rather than how much it weighs, because mass does not change. They can work out the mass of galaxies by measuring the distance between them and the speed they move at.
Recently, Jorge Peñarrubia, a senior academic at Edinburgh University, UK, and his team discovered something interesting: The mass of the Milky Way is only half as much as the mass of another nearby galaxy, Andromeda. This seems strange, and dark matter may explain why.
Finding out more about dark matter could help us understand how the universe began, but this is not easy. Lots of scientists with different types of expert knowledge are working on the problem.
We can’t see dark matter, it’s very difficult to measure and we can’t find out its mass. Unlike stars, dark matter doesn’t produce or reflect light. But we can make a good guess that it is there because of the way things move and the way light bends. Experts now think dark matter may be very different from the matter that we find on Earth. There may also be five times as much dark matter in the universe as ordinary matter.
1.Something that weighs 15kg on Earth weighs about ________ on Mars and ________ on Jupiter.
A. 7.5 kg, 45 kg B. 30 kg, 45 kg C. 45 kg, 7.5 kg D. 5 kg, 30 kg
2.The author mentions the masses of the Milky Way and Andromeda mainly to ________.
A. explain why the same object has a different weight on different stars
B. compare the distance between the Milky Way and Andromeda
C. show that studying dark matter could help to answer some scientific questions
D. support the idea that scientists prefer to talk about mass instead of weight
3.Dark matter is difficult to investigate because ________.
A. it travels at a very fast speed
B. we can’t see where it is or measure its mass
C. it’s hard to measure the light it produces and reflects
D. it is much bigger than ordinary matter in size
4.According to the text, dark matter ________.
A. could accelerate the speed of stars
B. could lessen the mass of objects in galaxies
C. makes up the entire universe and its stars
D. may help us identify the origins of the universe
高三英语阅读理解中等难度题查看答案及解析
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Most of us have looked up at the stars that fill the night sky and wondered whether we’re alone in the universe. Indeed, the question of whether there’ s life out there has been something humankind ’s been asking itself for countless years. But thanks to China’s Five-hundred-meter Aperture Spherical Telescope (FAST), the answer to this question may come a lot sooner than we expected.
The telescope has a huge round reflector, which measures 500 meters across and has a perimeter（周长）of 1.6 kilometers. Because of its great size, it would have been both difficult and inefficient to get FAST to move like a regular telescope. Instead, FAST’s designers came up with a great solution: its surface is made up of 4450 panels which can be individually adjusted. This clever design feature allows scientists to detect radio signals from any angle with a great degree of accuracy. “Panels can change their positions through connected wires and parallel （关联的） robots. We can control their position with an accuracy of 1 mm,” Zheng Yuanpeng, chief engineer of the telescope’s panel project, told Xinhua News Agency.
FAST’s engineers also had the task of finding a suitable location. As any interference would affect its ability to detect distant radio waves, it needed to be built in a remote area. Luckily, the perfect spot was found in the beautiful mountains of Guizhou Province. “There are three hills about 500 meters away from one another, creating a valley that is perfect to support the telescope," Sun Caihong, chief engineer of FAST’ s construction, told Xinhua.
And although it wasn’t yet fully operated, FAST had already made great discoveries by October 2017. Since 1967, only around 2000 pulsars （脉冲星） have been discovered, yet FAST had detected six more by October 2017. Once FAST is fully up and running, we may finally have the answer to one of the biggest questions in history.
1.What is the purpose of mentioning the question in Paragraph 1?
A.To introduce the new giant telescope.
B.To explain why there is life in universe.
C.To remind readers to think about the life in space.
D.To emphasize the question that should be answered.
2.What can we know from Paragraph 2?
A.The telescope is made up of many panels.
B.The area of FAST is about 800 square kilometers.
C.The engineer can handle FAST’s position accurately.
D.The individual panel helps scientists catch radio signals.
3.Why was FAST built in Guizhou?
A.Because Guizhou is a remote province.
B.Because Guizhou has an ideal valley.
C.Because Guizhou has beautiful mountains.
D.Because Guizhou has the ability to build it.
4.What does the last paragraph mainly talk about?
A.FAST’s timeline. B.FAST’s future.
C.FAST’s operation. D.FAST’s discoveries.
高三英语阅读理解中等难度题查看答案及解析
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1
When we look at the sky and see a bright light moving quickly across it or coming towards the earth, we talk about seeing a “shooting star” or a “falling star”. These moving lights are not, in fact, stars at all. They are small pieces of matter from outer space, which burn up as they enter the Earth’s atmosphere. The correct name of them is meteoroids. Any pieces that make it to the Earth’s surface without completely burning up are known as meteorites. A meteor is actually the name given to the light we see when a meteoroid is burning up.
When a meteorite hits the Earth at speeds between 11 and 72 kilometers a second, it can do amazing damage. A very large meteorite could knock the earth out of its orbit. If this happened, all life on Earth would probably become extinct（灭绝）. The path we follow around the Sun would change and as a result the Earth would become either much hotter or much colder. This change in temperature would affect sea levels and the amount of water in rivers. There would either be huge floods, which would cover most of the land with water, or the oceans would dry up and there would be a drought, which means a long period of time without rain. Either way, nothing could survive. If a large meteorite landed in the sea it would almost certainly cause tsunamis, which would race towards the land, destroying everything in their paths.
Although it is unlikely the Earth will be struck by a meteorite large enough to do that kind of damage, there is evidence of fairly large meteorites hitting the Earth in the past. In 1908 a large area of forest in Tunguska, Siberia was destroyed by a meteorite that came apart just before it hit the ground. The moon, however, has about three billion craters陨石坑caused by meteorites impacting影响 its surface. The reason more meteorites have reached the surface of the moon than the surface of the Earth is that the moon does not have enough atmosphere for the meteorites to burn up in. some of the meteorites that have reached the Earth’s surface have done considerable damage. Some scientists believe it was a change of climate caused by meteorites hitting the Earth that resulted in the extinction of the dinosaurs and other large prehistoric animals.
Scientists are especially interested in meteorites because they contain information about the solar system. It is widely believed by scientists that most meteorites are produced by collisions（碰撞） between asteroids (small planets). These collisions probably happened many billions of years ago. This means the physical and chemical structure of a meteorite can give scientists information about the early days of the universe.
【小题1】 The story is about ___.
A. floods caused by meteors
B. matter from outer space
C. life on Earth millions of years ago
D. meteorites that have damaged the moon
【小题2】 The Earth has ___.
A. three billion craters
B. fewer craters than the moon
C. more craters than the moon
D. a thinner atmosphere than the moon
【小题3】 Some scientists believe the dinosaurs became extinct because ___.
A. they were hit by meteors
B. meteorites landed on their nests
C. meteorites landed and changed the climate
D. they could no longer breathe the atmosphere
【小题4】 Meteors are ___.
A. small planets
B. the same as asteroids
C. from broken parts of asteroids
D. the light we see when meteoroids hit our atmosphere
高三英语简单题查看答案及解析
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The night was dark, though sometimes the moving clouds allowed a star or two to be seen in the sky.The poor men held on to any bit of ____ they could find. They called to the Marie for but she was far the reach of the human voice. At one o’clock in the morning suddenly some were seen in the distance: another ship! The shouts of the were heard on board, and willing hands pulled them out of the water. The of the ship that had arrived at the scene to save their lives was Ellen. What had her to the exact spot the darkness and the pathless sea? Her captain had known of the wreck and had, indeed, to sail away from it. But let him speak for himself.
“ I was forced by the wind to change my course, a small bird flew across the ship once or twice and then flew at my face. I of this until exactly the same thing happened a second time, caused me to think it rather . While I was this , the same bird, for the third time, made its appearance and flew in the same way as before. I was then to change my course back to the original one. I had not gone far I heard a strange voice; and when I tried to where they came from, I found I was in the middle of people who had been shipwrecked. I immediately did my best to save them.”
1.A. land B. grass C. hope D. wood
2.A. food B. help C. rest D. stop
3.A. off B. out C. beyond D. from
4.A. people B. lights C. ships D. houses
5.A. sailors B. captains C. rescuers D. swimmers
6.A. name B. owner C. captain D. finder
7.A. ahead of time B. at times C. on time D. in time
8.A. brought B. carried C. kept D. caused
9.A. in B. on C. through D. around
10.A. everything B. nothing C. something D. Anything
11.A. attempted B. managed C. allowed D. demanded
12.A. Just as B. In case C. Only because D. Even though
13.A. paid no attention B. took good care C. took no notice D. kept close watch
14.A. which B. what C. that D. this
15.A. Interesting B. funny C. friendly D. unusual
16.A. searching B. expecting C. considering D. studying
17.A. back B. about C. up D. down
18.A. forced B. decided C. persuaded D. forbidden
19.A. when B. until C. then D. while
20.A. listen to B. search for C. make sure D. look out
高三英语完型填空中等难度题查看答案及解析
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Do you enjoy seeing the stars twinkling at night ? Or do you love the ocean and sea, diving and racing with lovely dolphins? With heavy burdens on their shoulders, teenagers find it hard to pull out. Even if they are free, they prefer to occupy themselves with computer games or watching TV. How to get children away from screens is a great concern for parents. Now there is some good news for those concerned parents and teachers.
A campaign is being launched to encourage children to surrender 30 minutes of screen time a day to head for the great outdoors.
The newly formed Wild Network – a collaboration of nearly 400 organizations – is attempting to attract youngsters away from television and computer screen and into fields, woods and parks.
Organizers say it is the UK's biggest ever campaign to reconnect children with nature and outdoor play, and claim it could help improve fitness, mental alertness and general well–being.
A documentary film, Project Wild Thing, will herald the launch at more than 50 cinemas across the UK from Friday. It looks at the increasingly fragile link between children and nature.
Members of the network include the National Trust, RSPB, Play England and the NHS sustainable development unit.
Andy Simpson, chairman of the Wild Network, said: "The tragic truth is that kids have lost touch with nature and the outdoors in just one generation. Time spent outdoors is down, roaming ranges have fallen drastically, activity levels are declining and the ability to identify common species has been lost."
Suggestions of how to get more time in nature include collecting conkers(板栗), camping or snail racing, and observing autumn colour on trees.
From January, the network will aim to make suggestions to politicians on how government can do more to get children muddy and bright-eyed.
This is not the first time the message of less screen, more play has been brought up. Children in the 1980s were entreated to do the same by the BBC TV series Why Don't You, which somewhat confusingly called on its viewers to "switch off your TV set, and go do something less boring instead".
1.What is the main purpose of the campaign in UK?
A. To save 30 minutes for watching TV programme each day.
B. To encourage children to play outdoors.
C. To see the documentary film, Project Wild Thing.
D. To teach students how to learn more efficiently in schools.
2.According to the organizers of Wild Network, there will be many advantages from the campaign except _______.
A. improving health conditions
B. keeping touch with nature
C. learning more about wildlife
D. teaching children how to make full use of their spare time
3.The underlined part “ to get children muddy and bright-eyed ” means “_______ ”.
A. to make children covered with mud
B. to urge politicians to do more things for children
C. to encourage children to take part in outdoors activities
D. to help children identify common species
4.Which of the following could be the best title for the passage?
A. A new campaign. B. Less screen, more play outdoors.
C. A newly formed Wild Network. D. Children get to know wild things.
高三英语阅读理解中等难度题查看答案及解析
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If you look around the streets of London, you’ll see the many methods people use to move around. 1. Now there’s a new addition: electric, or e-scooters (滑板车).
This traditional children’s vehicle has become more complicated over the years. And now, with the addition of a small electric motor, it’s become a cheap and easy mode of transport. Scooting around town can be fun and doesn’t involve much effort. 2. But considering accidents involving an electric scooter in the UK, questions are being asked about their safety and whether traffic laws should be changed.
Many e -scooter riders in the UK broke the law. Some have been seen on pavements, others on the road jumping red traffic lights, adding to the frustration of motorists stuck in jams. In the UK, the law states that riding one on the public highway or pavement is forbidden. But, despite this, it seems the increasing popularity of e-scooters means they can be seen everywhere. 3.
The UK government is looking at how safely they can be used on the road and is ‘reviewing’ the law. But its transport minister, Michael Ellis, has told the BBC that: “Micromobility products are appearing in countries across the globe and are an exciting innovation for which we know there is demand. 4. ”
5. Despite the fact that some of them can exceed 30mph, they sometimes only have one brake and no lights. However confident the rider may be, larger vehicles on the road make them unprotected. So it seems more work needs to be done to give e -scooters a safe and legal space to travel in.
A.The roads are already crowded.
B.We are mainly after economic benefits.
C.People seldom see e-scooter accidents in the UK.
D.However, safety must always be our top priority.
E.And now users are calling on regulations to be changed.
F.There’s no doubt there are dangers in riding a two-wheeled scooter.
G.It’s no wonder they’re becoming increasingly popular in cities around the world.
高三英语七选五中等难度题查看答案及解析
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"Take a look at these pictures, and see if you can _____ the criminal." The policeman said to the witness.
A. pick up B. pick off
C. pick out D. pick at
高三英语单项填空中等难度题查看答案及解析
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"Take a look at these pictures, and see if you can _____ the criminal． " The policeman said to the witness．
A．pick up B．pick off C．pick out D．pick at
高三英语单项填空中等难度题查看答案及解析
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If you often go to a gallery, it ______ well change forever the way you look at art.
A. may B. should C. will D. must
高三英语单项填空中等难度题查看答案及解析
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Have you always wanted to discover the night sky but just don't know where to start?If so,then Back Garden Astronomy SkyatMight , Week is for you!
Launching at the start of March,this new beginner's guide from BBC Sky at Night Magazine will introduce the wonders of Earth's constant companion in space,the Moon,in easy-to-do, nightly observing instalments.
Just sign up and each day from Monday 2 to Monday 9 March we'll send you a no-nonsense email newsletter that will help you discover the wonders of our planet's natural satellite.We'll show you how to judge the Moon's movement across the sky,and introduce you to some of the most spellbinding sights on its surface.
We'll guide you to the Moon's most dramatic craters and seas,allowing you to discover for yourself the rugged locations that attracted the Apollo astronauts.
Each day during Back Garden Astronomy Week you'll also get essential observing tips and a fascinating insight into the Moon-explaining everything from what's behind its ever-changing phases to how old we think it is.
Sign up today to start your journey of discovery and we'll send you a FREE 62-page digital starter pack including a Guide to the Moon before Back Garden Astronomy Week starts!
SIGN UP TODAY!
Visit www.skyatnightmagazine.com/backgarden to sign up in a few easy steps.
1.Who is the Back Garden Astronomy Week intended for?
A.Researchers studying the universe.
B.Anyone interested in space.
C.Teenagers interested in the Moon.
D.New beginners interested in the Moon.
2.After signing up,what can you receive from this project before Monday 2?
A.Essential observing tips.
B.A free Guide to the Moon.
C.A no-nonsense email newsletter.
D.A chargeable digital starter pack.
3.Where can you most probably read this passage?
A.On a website.
B.On a university bulletin board.
C.In a text book.
D.In a travel guide book.
高三英语阅读理解中等难度题查看答案及解析