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            • 1．
              Talk to the animals
              All kinds of animals can communicate in one way or another． Maybe you have heard about the way bees dance around to send messages to each other and the ways dogs bark （犬吠） to give warnings or to be friendly． But did you know about infrasonic （次声的） communication
              used by elephants？ This is how it works：
              Humans hear low sounds like the thunder rumbling （隆隆作响） in the sky． But we don't hear sounds lower than that． However， animals such as elephants can hear much lower sounds than humans can． And what's more， they can make lower sounds as well， and they use them to communicate with each other． This is known as infrasound．
              The amazing thing about infrasound is that it travels over several kilometers． Sounds which have a higher pitch （音高）， like the ones people can hear， don't travel well through walls，
              leaves， trees， and so on， which is why we can't hear sounds from more than 100meters away． But infrasound is much "stronger"， and things like trees have no effect on it． Therefore it can travel much further． Elephants can hear infrasonic calls from 4kilometers away!
              There have been reports of people watching groups of elephants feeding or resting and then the elephants suddenly all stopped whatever they were doing for no reason at all． They obviously heard a warning call from a long way away， but the people didn't hear a sound． In places like a zoo or wildlife park where you can get nearer to animals， it is easier to sense when infrasonic sounds are made． When you stand near mother elephants with their babies in a zoo you may notice a slight rumbling in the air every few minutes - not loud or strong， but clearly noticeable． This is infrasonic communication - the mother elephants "talking" to their babies．

              (1) How do elephants communicate with each other？ ______
              A．By dancing around to send messages．
              B．By using infrasonic communication．
              C．By different sounds of rumbling．
              D．By different ways of barking．
              (2) What is the amazing thing about infrasound？ ______
              A．It goes into the sky．
              B． It travels very far．
              C． It sounds stronger．
              D． It stops at walls．
              (3) Humans can hear ______ ．
              A．sounds with a higher pitch
              B．sounds from 100meters away
              C．lower sounds than elephants can
              D．lower sounds than thunder rumbling
              (4) In places like zoos， ______ ．
              A．elephants don't need to make infrasonic sounds
              B．it is easier for elephants to make infrasonic sounds
              C．mother elephants don't let people stand near their babies
              D．humans can sense infrasonic sounds when they are made
              难度：较易
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            • 2． Time to dance
              Are you the kind of person who likes to move with music？It's a natural thing to do．Even little children start jumping up and down when they hear music．
              Scientists say that animals dance，too．（46） ______ ．The"dances"of animals send messages to other animals．But when people dance，they express feelings about life and love，or about these very human experiences．
              （47） ______ ．For one thing，dancing is good for you physically．It makes your heart work and makes you breathe fast．（48） ______ ．If you go dancing often，you can keep physical fit．You may feel very tired after dancing，but you'll probably also feel relaxed and happy．This is another important point about dancing．It gives you a chance to express your feelings and feel better about yourself．（49） ______ ，dancing helps those feelings go away．
              （50） ______ ．Some dances are for couples and some are for groups．But all kinds of dances give you a chance to meet new people or do something enjoyable with friends．

              A．But their dancing is different
              B．And finally，it's a social activity
              C．If you are angry or upset about something
              D．It also makes you use your arms and your legs
              E．Dances are good for you in many ways．
              难度：较易
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            • 3． Every time we turn on the TV or take a ride in a car，we could be adding to a problem called acid rain（酸雨）．In this article，we'll learn something important about acid rain．
              The formation of acid rain
              When people use fuels （燃料），such as coal and gasoline（汽油），poiso nous gases are given off．When these gases come together with rain，acid rain forms．Many power stations burn fuels in order to create the electricity（电） that we use in our homes and offices every day．Cars and trucks also send these gases into the air when they burn gasoline．When rain meets these gases，harmful things called acids form．This is acid rain．
              The harm of acid rain
              Acid rain destroys everything that it touches．It poisons our rivers，ponds and lakes and oceans along with the life in them．It pollutes our soils and crops，harm trees，and can even kill fish and plants．Acid rain also eats away at our buildings．
              The prevention of acid rain
              We need to reduce and even stop the pollution that gets into our air．Turn off lights，televisions and other electrical appliances（电器） if we are not using them．Walk and take a bike whenever possible．If we are travelling a long distance，take a bus or train to save fuel．
              As research shows，acid rain harms our environment．But people everywhere can take small steps now to help protect our environment for future generations．
              Whenever we use electricity or drive our cars we may add something bad to the air around us．And even worse，we may cause a terrible problem-acid rain．
              The formation of acid rainWhen fuels，such as c oal and gasoline are burnt，harmful gases are sent into the air．When these gases （1） ______ with rain，acid rain forms．
              The harm of acid rainAcid rain is greatly （2） ______ to the environment．It makes our rivers，ponds and lakes and oceans dirty and （3） ______ the death of fish and plants．And it can corrode （腐蚀） the buildings we live in．
              The prevention of acid rain Trying to prevent the pollution that gets into the air is（4） ______ ．Keep the electrical appliances off while they are not in use．We can also use different ways of traffic to make less use of fuels．
              Research tells us that acid rain harms our environment．So people around the world can take small steps now to make a （5） ______ to our kids．
              难度：较易
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            • 4． Maybe there is no better time for us to think about the steps our family can take to protect the environment．In fact，in our daily life，there are many kinds of easy ways we can think of to save money and protect the environment．
              Make our houses more airtight （密封的）．If so，it will stop temperature loss and keep the houses warm in winter．
              Buy newer fridges and air conditioners，especially when the old ones are more than five years old．New ones can save twice as much energy as old ones．
              Change bulbs．LED light bulbs can give brighter light with less energy and can be used for a longer time．
              Clothes can be washed clean in cold water with today's detergents．Using hot water takes five times the energy and produces five times the carbon （碳）．
              If we all take action to save energy and reduce consumption in our daily life，it will not only save money but also help protect the environment
              Living Tips for Better（56） ______
              Introduction It's not （57） ______ for us to think of ways in our daily life．
              Main
              Body              		 Ways of（58） ______
              money and protecting the environme              		 ★To stop temperature loss and keep the houses （59） ______ in winter，it's better to make our houses more airtight．
              ★As old electrical appliances（电器） （60） ______ too much energy，it's a good idea for us to（61） ______ them for new ones after they serve us for more than five years．
              ★LED light bulbs can give brighter light as well as save energy，and they have a（62） ______ lifespan（寿命）．
              ★We should wash clothes with cold water because it takes（63） ______ energy and produces lower carbon．
              （64） ______ To protect the environment，we need to take action to save energy and （65） ______ consumption．
              难度：较易
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            • 5． Do you think getting cold can give you a cold？Is it bad to drink milk when you have a cold？
              Ranit Mishori，a family medicine doctor in Washington，says colds are more common in winter，but not because of low temperatures．The cold weather just means people stay inside more．People like staying together and may get the common cold virus if they shake hands，sneeze（打喷嚏） or cough near one another．
              Adults generally get two to three colds a year．Children are likely to catch four or five．Dr Mishori says some people wrongly believe they can become protected from colds for the rest of their life once they get the virus one time．
              There is still no cure for the common cold．But Dr Mishori says there are ways to feel better sooner．
              If you get a cold，you start taking about two grams of Vitamin C a day．There is evidence（证据） that it might shorten the number of days that you will be having the cold．Dr Mishori says honey，bears'favourite food，can also help．She says honey seems especially effective（有效的） in children with colds．
              Have you ever heard the old saying"feed a cold，starve（挨饿 a fever"？Dr Mishori says this is not necessarily a good rule to follow．She says if you have a cold but do not feel hungry，then don't eat．
              According to Dr Mishori，you have to drink a lot．You can drink water or youcan drink tea-anything that gets into your body．That's very important．
              But what about drinking milk during a cold？Mishori says，"Drinking milk during a cold possibly does make you uncomfortable．But clearly if you have a baby and that's all it drinks，you should not stop giving the baby milk．"
              Title：What do you know about a cold？
              The （1） ______ of people having colds in winter It is because of the cold virus rather than low temperatures that people have a cold in the cold weather．
              Ways of people
              getting the cold virus              		 The common cold virus is （2） ______ from one person to another by ways of handshakes，sneezing or coughing．
              More details
              about colds              		 ●Adults are less likely to catch a cold than children．
              ●Once getting the virus can not（3） ______ you from colds for the rest of life．
              Ways to help with
              common colds              		 ●Take about two grams of Vitamin C a day and you will soon recover from your cold．
              ●Honey may be of especial effect to children with colds．
              ●（4） ______ eating if you are not hungry when you have a cold．
              ●Drink much water or tea every day．
              ●It's （5） ______ that drinking milk might make you feel more uncomfortable．
              难度：较易
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            • 6． China is the world's largest emitter（发射体） of carbon pollution．But Beijing has worked to improve environmental management and reduce pollution in recent years．
              China has made a plan to be a"green development"model over the next five years，increasing the share of non-fossil fuels（非矿物燃料）．The plan is to use wind，solar，biomass，water and geothermal energy．Beijing also says it will find cleaner ways of burning fossil fuels like coal．
              China is already the global leader in clean energy investment．According to a new government report，the share of non-fossil fuels has reached 11.2percent in 2015．That's an increase of 1.4percent from 2014．China has the biggest solar photovoltaic cell capacity and the largest wind power market．The number of water power stations in China is about a quarter of the world's．The rapid development of clean energy has helped China's carbon emissions per unit GDP reduce．
              "From 2005to 2014，China's energy use per unit GDP went down 29.9percent，and carbon dioxide emissions（二氧化碳排放） per unit of GDP went down 33.8percent．At that time，the numbers of developed countries only went down about 15percent，and the world average level did not change much．So it should be said that China has achieved a lot in cutting carbon pollution，especially in cutting the pollution per unit of GDP，"He Jiankun，deputy director of National Experts Committee on Climate Change，said．
              阅读以上信息，用恰当的词完成下面的短文，每空一词．
              China has tried to improve environment and reduce pollution．Beijing has （61） ______ to be a"green development"model over the next five years．China is already the global leader in clean energy investment．Clean energy in China has developed （62） ______ these years and the use of non-fossil fuels in China has （63） ______ regularly．The deputy director of National Experts Committee said that from 2005to 2014China's carbon pollution per unit GDP（64） ______ much more than developed countries and the world average level．He said that China has made a great （65） ______ in protecting the environment．
              难度：较易
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            • 7．
              In the past，man did not have to think about the protection of his environment．There were not many people on earth，and natural resources seemed to be unlimited （无限的）．
              Today，things are different．The world has become too crowded．We are using up our natural resources too quickly，and at the same time we are polluting our environment with dangerous chemicals．If we continue like this，human life on earth will not survive．
              Everyone realizes today that if too many fish are taken from the sea，there will soon be none left．Yet，with modern fishing methods，more and more fish are caught．We know that if too many trees are cut down，forests will disappear and nothing will grow on the land．
              We realize that if rivers are polluted with waste products from factories，we will die．However，in most countries，waste products are still put into rivers or into the sea，and there are few laws to stop this．
              We know，too，that if the population of the world continues to rise at the present rate，in a few years，there will not be enough food．
              What can we do to solve these problems？
              If we eat more vegetables and less meat，we will easily get more food．Land that is used to grow crops can feed five times more people that land where animals are kept．
              The world population will not rise so quickly if people use modern methods of birth control．
              Finally，if we educate people to think about the problems，we shall have a better and cleaner living place in the future．
              The importance of（46） ______ the environment
              Problems
              (1) More fish being （47） ______
              (2) More （48） ______ being cut down．
              (3) More waste products being put into rivers
              (4) More（49） ______ being born Causes The world is becoming too（50） ______ Modern methods make the situation （51） ______ （52） ______ We human beings （人类） will not survive on the earth． Solutions 1．Eat more vegetables and less meat so that more food will be（53） ______ for everyone． 2．Use modern methods of （54） ______ control so that the population will not grow too fast． 3．Educate people so that the （55） ______ will be better and cleaner．
              难度：较易
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