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I ____ the latest Harry Potter book all day. I'm dying to know what happens in the end!

 

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Because the low latitudes of the Earth, the areas near the equator, receive more heat than the latitudes near the poles, and because the nature of heat is to expand and move, heat is transported from the tropics to the middle and high latitudes. Some of this heat is moved by winds and some by ocean currents, and some gets stored in the atmosphere in the form of latent heat. The term “latent heat” refers to the energy that has to be used to convert liquid water to water vapor. We know that if we warm a pan of water on a stove, it will evaporate, or turn into vapor, faster than if it is allowed to sit at room temperature. We also know that if we hang wet clothes outside in the summertime they will dry faster than in winter, when temperatures are colder. The energy used in both cases to change liquid water to water vapor is supplied by heat – supplied by the stove in the first case and by the Sun in the latter case. This energy is not lost. It is stored in water vapor in the atmosphere as latent heat. Eventually, the water stored as vapor in the atmosphere will condense to liquid again, and the energy will be released to the atmosphere. In the atmosphere, a large portion of the Sun’s incoming energy is used to evaporate water, primarily in the tropical oceans. Scientists have tried to quantify this proportion of the Sun’s energy. By analyzing temperature, water vapor, and wind data around the globe, they have estimated the quantity to be about 90 watts per square meter, or nearly 30 percent of the Sun’s energy. Once this latent heat is stored within the atmosphere, it can be transported, primarily to higher latitudes, by prevailing, large-scale winds. Or it can be transported vertically to higher levels in the atmosphere, where it forms clouds and subsequent storms, which then release the energy back to the atmosphere
7. The underlined word “prevailing” in the second paragraph is closet in meaning to _______

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The number of people accessing the State’s and community’s priority policies and  programmes is increasing, said Minister of Labour, Invalids and Social Affairs Dao Ngoc Dung. Vietnam has around 6.2 million people over the age of two with disabilities, making up 7.06 per cent of the country’s population. Of those, 28 per cent are severely disabled, 58 per cent female, 28 per cent children and 10 per cent living in poverty. Most live in rural areas and many are victims of Agent Orange.  Minister Dung said in the past, the State, the Party and Vietnamese people had paid much care to people with disability. Vietnam ratified the United Nations’ Convention on the Rights of People with Disability in 2014. In March this year, the country ratified the International Labour Organisation’s Convention 159 about jobs for people with disability. It strongly confirmed Vietnam’s commitment ensuring the disabled would not be discriminated at work.  Last month, the Secretariat Committee issued the Instruction 39 about the Party’s leading work on affairs related to people with disability. The National Assembly later ratified the amended Law on Labour with many adjustments relating to disabled people. Dung said that every year, millions of disabled people receive an allowance from the State and all of provinces and cities had rehabilitation centres. Attending the event, Truong Thi Mai, head of the Party Central Committee’s Commission for Mass Mobilisation, said besides the achievements, Vietnam still sees many obstacles. Infrastructure is still limited demand for people with disability and many live below the poverty line depending heavily on their families.  Mai asked organisations to improve education to raise people’s awareness of the meaning of supportive work to people with disability. This year, more than VNĐ17 trillion (US$735.4 million) from the State budget was allocated to provinces and cities to implement policies for people with disability, according to the Ministry of Labour, Invalids and Social Affairs.  The Ministry of Planning and Investment on Thursday launched the programme “White stick for Vietnamese visual impaired people”. Its aim is to present one million white sticks to visually impaired people across the country. Training to use the device will also be provided. Minister of Planning and Investment Nguyen Chi Dung said the ministry will listen to disabled people’s demands and wishes and put them into its policies. Deputy chairwoman of the National Assembly Tong Thi Phong said Vietnam has committed to developing socioeconomy, taking care of social equality and improving social management ability.  
3. The word “It” in paragraph 2 refers to _____

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Rome is the capital of Italy. This sprawling modern city has many ancient monuments. Rome’s history goes back more than 2,500 years. Because of its age, Rome is often called the Eternal City. Rome’s many art treasures and historic buildings make the city an important center of European culture. In ancient times, Rome was the center of a mighty Roman empire. The empire lasted nearly 500 years, into the ad 400s. Roman armies conquered the lands that are now Italy, Greece, Great Britain, France, and Egypt. The Romans built many roads from Rome to distant parts of their empire. This network of roads led to a saying that “All roads lead to Rome.” The Roman Empire’s influence is still present. The Romans spread their language, Latin, throughout Europe. Latin is the basis for Italian, French, Spanish, and other European languages. The ancient Romans were great builders. Several of their buildings still stand today. They are among Rome’s famous landmarks.The Pantheon is a temple dedicated to the many Roman gods of mythology. The Roman Colosseum is a four-story amphitheater. An amphitheater is like a football stadium. The Colosseum is where Roman citizens once watched gladiators fight to the death. The Roman Forum was the political center of ancient Rome. The senate building and law courts were there, along with shops and religious buildings. Many artists painted in Rome. The most famous of them is Michelangelo. He lived 500 years ago. Thousands of people visit Rome each year to see his art. Visitors to the Vatican stare in wonder at the beautiful murals that Michelangelo painted on the ceiling of the Sistine Chapel. The murals show scenes from the first book of the Bible, the Book of Genesis. Vatican City is the headquarters of the Roman Catholic Church. The pope lives at the Vatican. He is the head of the Catholic Church. There are more than a billion Catholics worldwide, making Roman Catholicism the largest Christian religion. Vatican City is an independent country within Rome. It is the smallest country in the world.
2. Rome is made an important center of European culture ______

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England has had a democracy for a long time. Until 1918, however, women were not allowed to vote in it. The right to vote is called ‘suffrage’ and the English women who fought (1) ____ and won that right were called “suffragettes”. The suffragette movement was led by Emmiline Pankhurst. In 1903, she founded an organization called the Women’s Social and Politica Union (WSPU). Members of the WSPU went to the Prime Minister to (2) ____ suffrage, but he told them to “be patient”. The suffragettes were not (3) ____.They wanted change immediately. The fight for the vote for women became intense and sometimes violent. In 1908, two suffragettes (4) ____ themselves to the fence outside the Prime Minister’s front door! They were arrested and spent weeks in jail. In 1912, hundreds of women took to the streets of London. They broke shop windows and even threw Stones at the Prime Minister’s house. Thousands of suffragettes were jailed for this and similar actions over the years. World War I (1914-1918) proved to be an important event for the women’s movement. Women contributed so much to the war effort as nurses’, factory workers, and at other jobs that more people became convinced of their right to vote. Women were (5) ____ given that right in January, 1918

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Seeing the glass as half full may mean a longer life, according to research suggesting that optimists not only live longer in general, but have a better chance of reaching 85 or older. People of an upbeat disposition have previously been found to have a lower risk of heart conditions and premature death. Researchers now say it could also play a role in living a long life. “A lot of evidence suggests that exceptional longevity is usually accompanied by a longer span of good health and living without disability, so our findings raise an exciting possibility that we may be able to promote healthy and resilient ageing by cultivating psychosocial assets such as optimism,” said Lewina Lee, the lead author of the study at Boston University School of Medicine. Writing in the Proceedings of the National Academy of Sciences, Lee and colleagues report how they analysed data from two previous long-term research projects, one involving female nurses and the other focused on a cohort of men. The former team compared lifespan for the most optimistic with the least, taking into account factors including age, sex, race, education, depression and other health conditions present at the outset. The results show the most optimistic group of women had a lifespan almost 15% longer than the least. As for the other project, when the team compared the fifth of men boasting the highest optimism scores with the least optimistic, they found the most positive men had lifespans almost 11% longer. But being optimistic was not only linked to a longer lifespan. For men and women it was also linked more specifically to living to 85 or older when health behaviours were taken into account, with the most optimistic group of women having 20% better odds of reaching age 85 than the least. Lee said it was not yet clear why optimism is linked to longevity. “In our study, healthier behaviours, fewer depressive symptoms, and more social ties only partially accounted for the association from optimism to exceptional longevity,” Lee said, adding there are likely to be other mechanisms at play, such as optimistic people coping better with stress. Dr Catherine Hurt, an expert in health psychology at City, University of London, said the study highlighted the importance of psychological wellbeing alongside physical wellbeing for living a long and healthy life.
7. Which of the following statements is TRUE, according to the passage?

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If you think you left the cliques behind in high school, think again. When it comes to  building friendships, men are more likely to return to their clique-y roots than women, according to a recent study published in the journal PLOS One. Researchers found that, in general, men seek to join all-male cliques, clubs or teams, while women prefer a more select, one-on-one relationship with a few close female friends. “Much of male friendship is about coalition building,” said Tamas David-Barett, lead author of the research paper, and member of the experimental psychology department at the University of Oxford.  After analyzing the profile pictures of nearly 112,000 Facebook users worldwide, David-Barett and his co-authors found that men were more likely to post a profile picture showing themselves with a large group of male friends. The study notes that such pictures are “arguably an essential element of the male-male coalition competition.” Conversely, women almost never posted a large group profile picture, but tended to display a photo with only one other female friend. As the paper explained, women “appear more often to focus their social capital on only one person at a time.”  So why are men and women different in the way they make friends? One hypothesis is the difference between the male and female brain. Typically, women tend to have a larger deep limbic system than their male counterparts. The limbic system is a network of nerves in the brain connected to instinct and mood. The limbic system controls basic emotions such as happiness and fear. Because this system tends to be larger in women, females are more in touch with their feelings and have an increased ability to connect individually with others.  According to the Wall Street Journal, other research indicates that females tend to build friendships off of emotional connections and are more apt to share intimate conversations. The male friendship, however, is established by doing things together, such as watching the game or hosting a barbecue. “Female friendships are characterized as more face-to-face. Women want to share and exchange,” said Irene Levine, a friendship expert. “They want to bond. Men, however, want to do things together. They want to go to spectator sports; they want to participate in sports together. They do things that are more side-by-side.” 
1. What does the passage mainly discuss?

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The idea of going overseas to study can be daunting, with visions of baffling languages or nights spent in isolation while you are gradually forgotten by your friends and family. (1) _________, the benefits of studying abroad - such as broadening your mind, improving your career prospects and making friends from all over the world - can make digging out your passport really rewarding. “Studying abroad is an eye-opening experience,” says Anna Boyd, event manager at The Student World. “Being (2) _________ in another culture, understanding differences and spotting similarities, living on a beach or in the mountains, (3) _________ will have an impact on every student.” Overseas study comes in many shapes and sizes. It might be a single semester abroad via an Erasmus programme, for example. Or you might elect to follow a full three- or fouryear degree programme. Whatever your ambition, the key is starting early. Some countries require specific combinations of A-levels from UK students. Germany looks for four A-levels including maths or science and one modern foreign language, for instance, while others, such as the US, value extracurricular activities. Starting our research well ahead (4) _________ time can help you make the right choices. “Getting involved in sports, arts and music is also worth considering, as well as gaining experience through volunteering and work placements,” says Boyd. In fact, applying to study abroad could even work to your advantage , for example, you might encounter lower (5) _______ requirements

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Can you name some countries having subtropical climate ___________ the world?

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In 1903 the members of the governing board of the University of Washington in  Seattle engaged a firm of landscape architects, specialists in the design of outdoor environments - Olmsted Brothers of Brookline, Massachusetts - to advise them on an appropriate layout for the university grounds. The plan impressed the university officials, and in time many of its recommendations were implemented. City officials in Seattle, the largest city in the northwestern United States, were also impressed, for they employed the same organization to study Seattle’s public park needs. John Olmsted did the investigation and subsequent report on Seattle’s parks. He and his brothers believed that parks should be adapted to the local topography, utilize the area’s trees and shrubs, and be available to the entire community. They especially emphasized the need for natural, serene settings where hurried urban dwellers could periodically escape from the city. The essence of the Olmsted park plan was to develop a continuous driveway, twenty miles long, that would tie together a whole series of parks, playgrounds, and parkways. There would be local parks and squares too, but all of this was meant to supplement the major driveway, which was to remain the unifying factor for the entire system. In November of 1903 the city council of Seattle adopted the Olmsted Report, and it automatically became the master plan for the city’s park system. Prior to this report, Seattle’s park development was very limited and funding meager. All this changed after the report. Between 1907 and 1913, city voters approved special funding measures amounting to $4,000,000. With such unparalleled sums at their disposal, with the Olmsted guidelines to follow, and with the added incentive of wanting to have the city at its best for the AlaskaYukon-Pacific Exposition of 1909, the Parks Board bought aggressively. By 1913 Seattle had 25 parks amounting to 1,400 acres, as well as 400 acres in playgrounds, pathways, boulevards, and triangles. More lands would be added in the future, but for all practical purposes it was the great land surge of 1907-1913 that established Seattle’s park system
1. What does the passage mainly discuss?

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Plastic bags are used by everybody. From a vegetable vendor to a designer store, everyone seems to use them. Even though they are one of the modern conveniences that we seem to be unable to do without, they are responsible for causing pollution, killing wildlife, and using up the precious resources of the Earth. But, most of us are blissfully unaware of the repercussions that are occurring and will take place in the future because of the plastic bags. Every once in a while, the government passes out an order banning store owners from providing plastic bags to customers for carrying their purchases, with little lasting effect. Plastic bags are very popular with both retailers as well as consumers because they are cheap, strong, lightweight, functional, as well as a hygienic means of carrying food as well as other goods. About a hundred billion plastic bags are used every year in the U.S. alone. And then, when one considers the huge economies and populations of India, China, Europe, and other parts of the world, the numbers can be staggering. The problem is further exacerbated by the developed countries shipping off their plastic waste to developing countries like India. Once they are used, most bags go into landfills. Each year, more and more bags are ending up littering the environment. Once they become litter, plastic bags find their way into our waterways, parks, beaches, and streets. And, if they are burned, they infuse the air with toxic fumes. About 100,000 animals, such as dolphins, turtles, whales, penguins are killed every year due to these bags. Many animals ingest plastic bags, mistaking them for food, and therefore, die. And worse, the ingested plastic bag remains intact even after the death and decomposition of the animal. Thus, it lies around in the landscape where another victim may ingest it. One of the worst environmental effects is that they are non-biodegradable. The decomposition takes about 400 years. No one will live so long to witness the decomposition of plastic! Thus, save the environment for the future generations as well as animals. Petroleum products are diminishing and getting more expensive by the day, since we have used this non-renewable resource increasingly. And to make plastic, about 60-100 million barrels of oil are needed every year around the world. Surely, this precious resource should not be wasted on producing plastic bags, should it? Petroleum is vital for our modern way of life. It is necessary for our energy requirements - for our factories, transportation, heating, lighting, and so on. Without viable alternative sources of energy yet on the horizon, if the supply of petroleum were to be turned off, it would lead to practically the entire world grinding to a halt. So, what can be done? A tote bag can make a good substitute for carrying groceries and the shopping. You can keep the bag with the cashier, and then put your purchases into it instead of the usual plastic bag. Recycling the bags you already have is another good idea. These can come into use for various purposes, like holding your garbage, instead of purchasing new ones. While governments may be working out ways to lessen the impact of plastic bags on the environment; however, each of us should shoulder some of the responsibility for this problem, which ultimately harms us. Plastics are not only nonbiodegradable, but are one of the major pollutants of the sea. For a clean and green environment, try to use alternatives to plastic whenever and wherever possible. Cut down your use of plastic, and do your bit to save our planet  
2. What is the synonym of the word “repercussions” in the first paragraph?

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It was at this time, 1876–1877, that a new invention called the telephone emerged. It is not easy to determine who the inventor was. Both Alexander Graham Bell and Elisha Gray submitted independent patent applications concerning telephones to the patent office in Washington on February 14, 1876. Bell, in Boston at the time, was represented by his lawyers and had no idea that the application had been submitted. Gray’s application arrived at the patent office a few hours before Bell’s, but Bell’s lawyers insisted on paying the application fee immediately; as a result, the heavily burdened office registered Bell’s application first. Bell’s patent was approved and officially registered on March 7, and three days later the famous call is said to have been made when Bell’s summons to his assistant confirmed that the invention worked. Alexander Graham Bell, one year younger than Lars Magnus Ericsson, had been born in Edinburgh. Bell’s interest in telephony came through his mother, who was deaf, and his father, Alexander Melville Bell, who was a teacher of elocution, famous for the phonetic transcription system he had developed to help the deaf learn to speak. The Bell family migrated to Canada in 1870; two years later Alexander Melville Bell was offered a teaching post at a school for the deaf in Boston in the United States, but he successfully recommended his son for the post instead. Father and son were at this time working together to try to discover whether sound could be made visible for the deaf with the help of telegraphy.  But many others had already been pursuing the idea of telephony for years. A resolution of the US House of Representatives in June 2002 claimed that Bell had nefariously acquired and exploited an apparatus, the “teletrophono”, invented by Antonio Meucci long before Bell and Gray. One damaging piece of evidence for Bell was that Meucci’s material had disappeared without trace from the very laboratory at which Bell was carrying out his experiments. In the 1880s, proceedings initiated by the American government charged Bell with “fraudulent and dishonest conduct” and claimed that his patent should be revoked. These proceeding were discontinued after Meucci’s death in 1889 and the expiry of Bell’s patent in 1893. A later investigation, published by A. Edward Evenson in 2000, claims that Bell’s attorneys acquired technical details from Gray’s attorneys that are said to have been added to Bell’s patent after it had been submitted. The whole saga has elements reminiscent of a thriller. One salient fact was that Bell saw no need to take out patents for the telephone in the Nordic countries. This meant that anyone anywhere there was free to manufacture and sell telephones. Bell presented the telephone before a large audience for the first time at the World Exhibition in Philadelphia in June 1876. In the audience was the physicist William Thomson, who in August that year presented Bell’s telephone to the British Association in Glasgow. In Sweden, on September 30 that year, Dagens Nyheter became the first newspaper to refer to “the speaking telegraph”, an apparatus that “plainly and clearly conveyed the words uttered at one end of the telegraph line to the other”. The first version of Bell’s telephone, as it was described in the patent application, was not suitable for practical purposes. Only after “a relatively thorough reconstruction”, to quote Hemming Johansson, could a telephone be designed for large-scale production. The Bell Telephone Company began operating on July 11, 1877. In the same month, the first useable Bell telephone arrived in Europe to be presented in Plymouth to the British Association by the chief engineer of the General Post Office, William H. Preece, in the presence of Bell himself  
5. The word “nefariously” in paragraph 3 can be best replaced by _____

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There are many thoughts on the origins of civilization. One of the major factors  involved was the increase in population. The development of techniques, primarily irrigation and food control, which permitted agriculture in special areas such as the flood plain of the Tigris and Euphrates rivers, made possible the support of large population. Once populations reach a certain number, the older pattern of social organization breaks down and new ones develop. Specifically the older system whereby each individual participated in food production and maintained a similar standard of living, and whereby kinship served as the basic method of social organization, was replaced by the occupational division of labor, political and religious hierarchies, public works such as road and public building construction, class systems, codes of law, markets, new forms of warfare, and urban centres. Allied with these important sociological traits are material traits, such as monumental architecture and development of science and, in many cases, metallurgy and writing systems.  The earliest civilization, Sumer, developed in the Middle East. This was the Bronze Age of the Old World, during which people first developed the art of metallurgy, civilization also arose in other parts of the Old World first in Egypt, China and India, and later in Europe and Africa. At this time, civilization also developed independently in the New World, in the Mexican area and in Peru and its neighboring areas.  In the Old World the Bronze Age was followed by the Iron Age, which saw the rise and fall of great empires and the shift of power from the Middle East to Greece and Rome and then to Western Europe. In the 1700s the Industrial Age began, leading directly to the modern civilization of today. 
3. Which of the following is NOT true according to the passage?

Each sentence has a mistake. Findit by chosing A B C or D

 Vietnam faces a challenge which it is the rapid increases of motor vehicles, particularly in the big cities

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We have ………………… time to get it finished.

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The concept of exotic holidays is not new. Cruises and other travel packages to tropical locations have long been popular and are more (1) ____ now than ever. The wealthy have gone on trips to exotic places since the 19th century, but now ordinary people have enough money for this kind of holiday. Holidaymakers are increasingly interested in doing something different and want more exciting (2) ____. A number of tour companies have responded with a new range of options, including African safaris. Going on a safari is a totally (3) ____ form of holiday. Accompanied by a safari guide, groups travel into the African wilderness to experience close up the thrill of the wild. Being so close to the animals is an once-in-a-lifetime experience. (4) ____ species, which are rarely seen outside the zoo, provide a great (5) ____

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Advances in mobile technology and social networking websites mean we spend more time online than ever before. If Facebook were a country, it would be the third largest in the world by population (The Economist, 2010). It is (1) ______ not surprising that so many psychologists, sociologists, and others are eager to give their thoughts on how this is impacting negatively on our society. The biggest criticism levelled at social networking is that young people are losing their offline friends to online friends (2) ______ are unable to provide the same deep connection and emotional support. However, a lot of research shows these criticisms are generally (3) ______. Allen et al. (2010) discovered that it is socially adjusted adolescents who are more likely to have a networking profile than those who are not. One study by the Pew Internet and American Life Project (2009) found that people are not (4) ______ offline friends with online companions but are using them to support their offline relationships. The study also found that social networks allow us to have discussions with a much more diverse set of people than in the real world, so we share knowledge with people from a wide (4) ______ of backgrounds

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To really figure out what a CV is, we first have to talk about what CV means. The  letters CV stand (1) ____ curriculum vitae which is Latin for “course of life.” When used in a job seeking context, a CV (also sometimes referred to as just a vita) is a detailed accounting of not only a person’s past history of education, experiences and (2) ____ but also related accomplishments and is generally used when an individual is looking for a job. (3) ____, a CV is a thorough and comprehensive document, detailing not only your education and work history, but also your achievements, awards, any honors you’ve been conferred and any and all of your publications.  A resume, on the other hand, is not so long. Ideally a good solid resume is about one page in length and can be submitted for almost any type of job (4) ____ the market. When you type up a resume, you’re usually just covering your work and educational history. You might include certain professional affiliations and possibly highlight (5) ____ major awards that relate to the job you’re applying for, but it’s usually a concise document. Short and sweet

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The Internet has truly transformed how students do their homework. (1)______ homework today still means spending time in the library, it’s for a different reason. Rather than using books for research, students today are (2)______ to the Internet to download enormous amounts of data available online. In the past, students were limited to their school’s (3)______ of books. In many cases, they got to the school library and found out that someone had already taken the books they needed. Nowadays, such inconvenience can be avoided since the Internet never runs out of information. Students, however, do have to (4)______ sure that the information they find online is true. Teachers have also benefited from the homework which is done on the Internet. They do not need to carry students’ papers around with them any more. This is because online (5)______ allow students to electronically upload their homework for their teachers to read and mark. Of course, this also means that students can no longer use the excuse that the dog ate their homework!

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Where humans have planted crops for food, unless they are organic, poisonous chemicals have been sprayed on them; insecticides are used to kill insect pests and herbicides are used to kill weeds. Fungicides fight off fungal diseases. Artificial fertilizers are added to the soil to increase the yield of the crops. If these chemicals are used in excess, some of them dissolve in rainwater and drain into rivers, streams and ponds, polluting the water and killing the wildlife. The “weeds” competing with the farmers’ crops include wild flowers and many of these have become endangered through the use of herbicides. Insects rely on plants for food and breeding sites so the number of these are affected by a reduction in the number of plants. Many birds depend on insects for food so the numbers of birds may be affected by the use of both insecticides and herbicides. One of the reasons why the Barn Owl is endangered is due to a shortage of insects and it may also be poisoned by eating insects affected by chemical sprays. The case of DDT and other chemicals known as organo-chlorines is well known. These were first used extensively in the 1950s, sprayed onto crops to kill insect pests. Unfortunately, after a few years, it was noticed that birds of prey were rapidly declining in numbers and thousands of seed-eating birds were dying. By the 1960s, the once common sparrow hawk was a rare bird in Britain. The sparrow hawk’s prey was the seed-eating birds which were carrying the poisonous insecticides in their bodies. Consequently, many sparrow hawks and other birds of prey were being indirectly poisoned by the chemical sprays. The organo-chlorines also caused many birds to lay thin shelled eggs, which cracked easily. Research showed that the chemicals were entering the food chains and being stored in the fat of the animals’ bodies. For example, a thrush may eat snails which have eaten a sprayed cabbage plant. The thrush may not have eaten enough poison to be actually killed but a sparrowhawk eating several thrushes accumulates so much of the poison that it is killed. The chemicals become more concentrated as they travel up the food chain. Even most humans still have small amounts of organo-chlorines in their fatty tissues although these chemicals had been withdrawn from use by 1976. They are still used, however, in some Third World countries. By the 1980s, the sparrowhawk population had recovered dramatically and it is once again a common bird. This example shows just how dangerous the use of chemicals in the environment can be. As mentioned earlier, some plants are endangered through collectors such as the Venus fly-trap and some tropical orchids, but most threatened plants have become so through the destruction of their habitat. Once very common plants have almost disappeared because of the way humans have changed the land. For example, the Egyptian Papyrus, a type of reed, had been used for thousands of years for all sorts of things such as paper, medicine, boats, baskets, food etc. Then, when changes in the irrigation methods on the river Nile were introduced, this valuable plant almost completely disappeared. It was thought to be extinct until 1968 when a few plants were found in an undisturbed waterway. Orchids have been also collected from rainforests to become household favourites, causing many species to become endangered.  
4. According to the passage, sparrow hawks are described as a species that ___________.

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Organisms play ________ important role in keeping the nature balanced.