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Sunlight is solar energy. Sunlight is needed for growing plants that you eat to get energy. Sunlight is also used to make clean electricity. Burning fossil fuels to make electricity pollutes our atmosphere and rivers. Fossil fuels are expensive and limited sources of energy. Nuclear fission is used to create enormous amount of heat and electricity. However, nuclear fission forms dangerous radioactive waste.
Sunlight offers many ways to get energy. A window can allow warm sunlight into your room. Solar water-heating systems can use sunlight to warm the water for your home, swimming pool

and school. Sunlight also warms the Earth and causes wind. Electricity can be made by wind generators.
Photovoltaic, or PV system use a type of material that converts sunlight into electricity. PV systems can power your air conditioner or a satellite like the International Space Station. PV systems are also used to run a calculator, recharge cell phone, or even power lightweight cars.
Sunlight is also changed into electricity by concentrating solar power or CSP systems. CSP systems have mirrors that focus the sunlight. The concentrated sunlight turns water into steam which turns a turbine that is connected to an electric generator. A CSP system usually uses sunlight to make steam. CSP power plants can store large amount of heat. The stored heat is used to make electricity at night. During cloud days, many CSP plants can also burn natural gas to provide the heat that is used to turn water into steam.
Sunlight provides the energy needed to grow plants and make large amount of environmentally friendly heat and electricity. Solar energy can provide power today and for a long time in the future.

The drawback of nuclear fission is that      

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Scientists have uncovered a new threat to the world’s endangered coral reefs. They  have found that most are incapable of growing quickly enough to compensate for rising sea levels triggered by global warming. The study suggests that reefs – which are already suffering serious degradation because the world’s seas are warming and becoming more acidic – could also become overwhelmed by rising oceans.  The research – led by scientists at Exeter University and published in Nature this week – involved studying growth rates for more than 200 tropical western Atlantic and Indian Ocean reefs. It was found only 9% of these reefs had the ability to keep up with even the most optimistic rates of sea-level rises forecast by the Intergovernmental Panel on Climate Change. “For many reefs across the Caribbean and Indian Ocean regions, where the study focused, rates of growth are slowing due to coral reef degradation,” said Professor Chris Perry, of Exeter University. “Meanwhile, rates of sea-level rise are increasing – and our results suggest reefs will be unable to keep up. As a result, water depths above most reefs will increase rapidly through this century.”  Sea levels rose by several inches over the past century and measurements indicate the speed of this increase is now rising significantly. Two key factors are involved: climate change is making ocean water warmer and so it expands. And as ice sheets and glaciers melt, they increase amounts of water in the oceans.  At the same time, reefs are being weakened by ocean warming and also by ocean acidification, triggered as the seas absorb more and more carbon dioxide. These effects lead to bleaching events that kill off vast stretches of coral and limits their ability to grow.  “Our predictions, even under the best case scenarios, suggest that by 2100, the inundation of reefs will expose coastal communities to significant threats of shoreline change,” said co-author Prof Peter Mumby of Queensland University. This point was backed by US marine scientist Ilsa Kuffner writing in a separate comment piece for Nature. “The implications of the study are dire. Many island nations and territories are set to quickly lose crucial natural resources.” 
1. Which of the following does the passage mainly discuss?

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The burglar cut the telephone wires for fear that I’ll call the police.

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U.S. population could increase from 323 million in 2016 to as high as 447 million by 2060—or fall as low as 320 million. It depends on how many immigrants are admitted over the next four decades, according to new report from the Census Bureau. According to the report, if current levels of immigration are maintained, the U.S. population will grow to 404 million by 2060. If immigration is cut in half, the population will rise to 376 million. If immigration increases by 50 percent, the population expands to 447 million. And if all immigration were to be halted now, the U.S. population would peak at around 332 million in 2035 and drop to 320 million in 2060. In the high-immigration scenario, the proportion of foreign-born residents would rise by 2060 to 21.6 percent of the population. If immigration is halted, the forecast shows only 4.6 percent of the population in 2060 being foreign-born. In all of the scenarios, the median age of the U.S. population rises from 37.9 to more than 40. The report projects that the number of people identifying as “white alone”—that is, respondents who check only the white ethnicity box on census forms—will continue to rise in the main, high, and low immigration scenarios. This increase results from the Census Bureau’s expectation that the children of Hispanic immigrants will probably, like the children of Italian, Polish, Greek, and other earlier immigrant groups, choose to identify increasingly as white. But the share of the population in the white alone category will decline in each scenario, due to faster increases in the numbers of Americans in the other racial and ethnic groups. America is an ideal, not a tribe  
4. The word “median” in paragraph 2 is closest in meaning to ______

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

When children get their first pair of glasses, they are often surprise to see that trees and flowers have sharp clear outlines

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Stabilisation work means the Leaning Tower of Pisa is leaning slightly less than it used to, experts have said. The tower, which has leaned to one side ever since it began to take shape in 1173, has lost 4cm of its tilt over the past two decades, according to a report from the surveillance group that meets every three months to give updates on the monument’s condition “Since restorative work began, the tower is leaning about half a degree less,” said Nunziante Squeglia, a geotechnics professor at the University of Pisa who works with the group. “But what counts is the stability of the tower, which is better than initially predicted.” The structure, which was badly damaged during the second world war, was closed to the public in 1990 over safety fears and did not reopen for 11 years. The surveillance group was set up in 2001 ago after Michele Jamiolkowski, an engineer of Polish origin, coordinated an international committee to save the landmark. The bell tower, a symbol of the power of the maritime republic of Pisa in the Middle Ages, was defective from the beginning due to the porous clay soil beneath its foundations. After three floors were completed, construction stopped and did not resume until 90 years later when workers started building additional floors on a diagonal to offset the lean. But work was again disrupted before finally being completed in 1372. The tower, located behind Pisa’s cathedral, attracts more than 5 million visitors a year. Reaching the top requires climbing 269 steps. The surveillance group’s work, which is funded by the non-profit Opera della Primaziale Pisana, includes improving the quality of the structure’s conservation and promoting research.
4. The word “offset” in paragraph 3 is closest in meaning to _____

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NASA continues to plan a flight to Mars. The technological challenge is immense, first  of all, because it will be very difficult to carry tons of material for the construction of a habitat. This is why NASA is looking for alternative solutions, such as the possibility of growing structures out of fungi to become our future homes in the stars. The concept of these “houses” is based on three distinct layers. The first is made of ice. It must protect people from radiation, but also provide the resources necessary for the second layer. This is made of photosynthesizing microbes or cyanobacteria, which produce oxygen for astronauts and nutrients for the final layer of mycelia. That last layer of mycelia is what organically grows into a sturdy home, first activated to grow in a contained environment and then baked to kill the lifeforms.  Researchers have already experimented with creating objects using mycelia. A team from Stanford and Brown universities grew a stool as part of a myco-architecture project at NASA’s Ames research center in 2018. After two weeks of growth, the stool looked like something that would have been long forgotten in a refrigerator. It was then baked that leads to a clean and functional piece of furniture. From the point of view of space conquest, mushrooms could also be used to filter water for future explorers and extract minerals. Once these prototypes are designed for other worlds, we can bring them back to ours. Building this kind of housing could reduce the huge carbon footprint of the construction industry. This research project is still in its infancy, but it shows us how scientists are able to broaden horizons, and it’s exciting.
3. According to paragraph 1, what is the discussed objective for NASA’s space nresearch?

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On April 3, 1972, a man came out of the Hilton hotel in Manhattan and started walking down the street. He stopped, (1)______ his hand with a strange object in it, put it to his ear and started to talk into it. This was the beginning of mobile phone (2)_______, more than 30 years ago. That man was Motorola’s project manager, Martin Cooper, who was (3)______ his 34th birthday that day. The strange object was the first mobile phone, which was nicknamed “the shoe” because of its unusual (4)_______. Mr. Cooper had gone to New York to introduce the new phone. The first call he made was to his rival, Joe Engel at AT&T’s research centre. Engel was responsible for the development of the radiophones for cars. “I called him and said that I was talking on a real mobile phone (5)_____ I was holding in my hand,” said Cooper. “I don’t remember what he said in reply, but I’m sure he wasn’t happy.” The quality of the call was very good, because although New York had only one base station at that time, it was being used by only one user – Martin Cooper.

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In the last five decades or so, the media and its influence on the societies, has grown (1)_______ with the advance of technology. First there was the telegraph and the post offices, then the radio, the newspaper, magazines, television and now the internet and the new media including palmtops, cell phones etc. There are positive and negative influences of mass media, which we must understand as a responsible person of a society. Before (2)___________ the influence of mass media on society it is imperative to explain the three basic functions of mass media; they are providing news/information, entertainment and education. The first and foremost function of the media in a society is to provide news and information to the masses, that is why the present era is some time termed as the information age (3)__________. People need news/information for various reasons, on one hand it can be used to socialize and on the other to make decisions and formulate opinions. Entertainment would be the other function of the mass media (4)______ it is mostly used by the masses to amuse them in present day hectic environment. Educating the masses about their rights, moral, social and religious obligations is another important function of mass media, which needs no emphasis. In present era of (5)__________ , majority of people in the society depends on information and communication to remain connected with the world and do our daily activities like work, entertainment, health care, education, socialization, travelling and anything else that we have to do

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New data from Akamai, an internet delivery and cloud services company, has exposed that the video game industry remains a growing threat vector for security breaches. Hackers have targeted 12 billion credential stuffing attacks against game websites within a 17-month period The rise and success of credential stuffing attacks is a result of people continuing to reuse the same passwords across multiple accounts. Google identified that 59% of online users reuse passwords. When a data breach happens, user credentials are exposed and can subsequently be found on the internet and the dark web. Cybercriminals use a bot with a list of exposed credentials against a website to gain access to an account on that site. The reason that gaming is subject to so many breaches is twofold; No. 1, most video game companies use low-friction authentication measures because increasing friction drives customer attrition and results in a loss of revenue. The second issue is that from a consumer perspective, gaming is seen as having a low financial risk and, as a result, gamers tend to use less secure passwords. Adding to these challenges is the fact that game developers are pressured to deliver more products at a faster pace, meaning there are more bugs and security issues for cybercriminals to exploit. This has created a perfect storm in the video game industry upon which hackers are all too eager to capitalize.   A significant number of gamers are young — elementary, middle, and high schoolaged — who are less security-conscious and more trusting of people they meet online. To them, privacy is a learned behavior leaving them open to exploitation. They may need to be taught best practices to safeguard their accounts and understand the risks of using weak passwords linked to the games they play. Providing a seamless online experience is paramount in the digital age and, as a result, many organizations balk at implementing robust security procedures for fear of alienating customers. The challenge for the video game industry is to find a balance between increased security without frustrating its players. One notable exception is Microsoft, which has deployed vigorous security measures with Xbox in line with the rest of its business. Without a fundamental change in approach from both gamers and the industry overall, the escalation of this problem shows no signs of slowing down.  
5. The word “They” in paragraph 4 refers to _____

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

Physicists is a fascinating course of study to follow

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Advertising helps people recognize a particular brand, persuades them to try it, and tries to keep them loyal to it. Brand loyalty is perhaps the most important goal of consumer advertising. Whether they produce cars, canned foods or cosmetics, manufacturers want their customers to make repeated purchases. [2] The quality of the product will encourage this, of course, but so, too, will affect advertising. Advertising relies on the techniques of market research to identify potential users of a product. [3] Are they homemakers or professional people? Are they young or old? Are they city dwellers or country dwellers? Such questions have a bearing on where and when ads should be placed. By studying readership breakdowns for newspapers and magazines as well as television ratings and other statistics, an advertising agency can decide on the best way of reaching potential buyers. Detailed research and marketing expertise are essential today when advertising budgets can run into thousands of millions of dollars. [4] Advertising is a fast-paced, high-pressure industry. There is a constant need for creative ideas that will establish a personality for a product in the public’s mind. Current developments in advertising increase the need for talented workers. In the past, the majority of advertising was aimed at the traditional white family - breadwinner father, non-working mother, and two children. Research now reveals that only about 6 percent of American households fit this stereotype. Instead, society is fragmented into many groups, with working mothers, single people and older people on the rise. To be most successful, advertising must identify a particular segment and aim its message toward that group. Advertising is also making use of new technologies. Computer graphics are used to grab the attention of consumers and to help them see products in a new light. The use of computer graphics in a commercial for canned goods, for instance, gave a new image to the tin can  
5. The author implies that the advertising industry requires ___________

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

Qualifications and experience are two the most important factors that help you get a good job

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The comings and goings of teenagers, while a frequent source of tension in the  parent–child relationship, are a crucial experience in the construction of social identities. For this age group, mobility is not just a practice that is socially determined – by social background, residential environment and schooling – but also a specific experience that durably shapes their relationships with the spaces and the social world they encounter.  Although mobility is a socialised practice, based on habits forged in the domestic, residential and school environments, it is itself a specific experience in teenage socialisation. At this age, mobility plays an important role in individuals’ learning of behaviours and ways of being, gradually reshaping the dispositions acquired during primary socialisation.  First of all, mobility affects teenagers’ ways of being and behaving within their peer group, which play an increasingly important role in teenage socialisation. At this age, peers become more and more involved in mobility practices: they are one of the key reasons for mobility but, above all, they become preferred partners in self-mobility situations.  Furthermore, the movements of teenagers, alone or in groups, gradually reshapes their dispositions vis-à-vis mobility, particularly those acquired in the domestic sphere. At this age, experiences in mobility have lasting effects on the future practices of teenagers. They sometimes help modify the dispositions of teenagers regarding transport modes. We could cite, among other examples, the case of a girl whose fear of the metro gradually diminished as a result of occasional trips with her best friend, who was more familiar with this mode of transport. These experiences also influence the spatial amplitude of future mobility, in particular preferences for travel within or outside one’s area of residence.  Lastly, mobility allows teenagers to discover the public domain, when it gives rise to interactions that take place under the gaze of an incidental audience and which are therefore subject to specific rules. In the course of their travels, teenagers gradually become familiar with these rules, and they mutually adapt their behaviours to those of other citizens so as to eventually find their place within the public domain. Listening to music on mobile phones on public transport, for example, is appropriate to a greater or lesser extent, depending on the circumstances at the time.
7. According to paragraph 5, what is the possible reason for teenagers’ effort to adapt in public domain?

Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions:
These days, most people in Britain and the US do not wear very formal clothes. But sometimes it is important to wear the right thing.
Many British people don't think about clothes very much. They just like to be comfortable. When they go out to enjoy themselves, they can wear almost anything. At theatres, cinemas and concerts you can put on what you like from elegant suits and dresses to jeans and sweaters. Anything goes, as long as you look clean and tidy.
But in Britain, as well as in the US, men in offices usually wear suits and ties, and women wear dresses or skirts (not trousers). Doctors, lawyers and business people wear quite formal clothes. And in some hotels and restaurants men have to wear ties and women wear smart dresses.
In many years, Americans are more relaxed than British people, but they are more careful with their clothes. At home, or on holiday, most Americans wear informal or sporty clothes. But when

they go out in the evening, they like to look elegant. In good hotels and restaurants, men have to wear jackets and ties, and women wear pretty clothes and smart hairstyles.
It is difficult to say exactly what people wear informal or formal in Britain and the US, because everyone is different. If you are not sure what to wear, watch what other people do and then do the same. You'll feel more relaxed if you don't look too different from everyone else.

Many British people wear freely when they     .

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A new study shows that urbanization shifts this seasonal cue in nuanced ways, with cities in cold climates triggering earlier spring plant growth and cities in warm climates delaying it. The study also found that the urban heat island effect, the phenomenon in which cities are warmer than their surroundings, is not the only culprit behind the shift, suggesting that other aspects of urbanization, such as pollution, changes in humidity and fertilizer runoff, may also influence plants’ seasonal patterns.  Researchers analyzed millions of observations of 136 plant species across the U.S. and Europe to study how regional temperature and the local density of people-a proxy for urbanization—affect when plants sprout leaves and blossoms. Their results revealed a complex story: Separately, warmer temperatures and higher population density each spurred earlier springs. A 3.6-degree Fahrenheit increase in temperature bumped up plants’ production of leaves and flowers by about five and six days, respectively. A fourfold increase in human population density advanced flowering and leaf production dates by about three days. But the team found that when these two factors worked together, local temperature had an outsized influence. In cold regions—areas with an average November-to-May temperature of about 18 degrees-plants produced leaves and flowers about 20 days earlier in locations with about 26,000 people per square mile, compared with equally frigid wildland. When an area’s average November-to-May temperature jumped to 68, however, leaves and flowers appeared four and six days later, respectively, in locations with about 26,000 people per square mile, compared with equally balmy wildland. In New York, for example, plants are likely sprouting leaves about 9.5 days earlier and blossoms eight days earlier than uninhabited regions with the same temperature. Jacksonville, in contrast, is likely pushing leaf production later by about one day and flowers by about half a day, with leaves appearing two days later and flowers a day later in Houston.  Even after accounting for urban heat islands, the team’s models revealed cities significantly affect plants’ springtime growth. “Not only are there other things going on, but they actually matter quite a lot,” said study co-author Brian Stucky, Florida Museum research scientist. Plants may not be the only organisms affected by seasonal shifts, he added. “Seasons are such a big part of our lives. We define our world around seasonal things. Those rhythms are what we think of as the normal way the world works.” 
8. Which of the following can be inferred from the passage?

Each sentence has a mistake. Find it by choosing the letter A, B, C or D.

Reading brings a variety of benefits because of readers can gain many lessons and much knowledge from books.

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In all the debate about conservation of natural landscapes, we must not forget that the 19th century also saw the development of interest in the cultural past. Although archaeology was around 100 years old at this point, at least in the Old World, it was largely an exercise in treasure hunting - digging up the treasures of the past as curiosities for museums or for the private collections of those who funded the dig. Changes in attitudes and law throughout the 19th century meant that monuments and artefacts were becoming part of the study of the past, no longer merely trinkets and curiosities, but indicators of a culture’s development and identity. Modern archaeology would not arrive until the 20th century and the concept of an archaeological landscape is younger still. The first laws to protect and conserve cultural heritage came into place in the late 19th and early 20th centuries in the developed countries. In the US, the first such law was the Antiquities Act in 1906 which gave the office of president the power to set aside areas of land as protected cultural assets, known as “National Monuments”. This law was in place until 1979 when it was replaced with the Archaeological Resources Protection Act but several other laws came into place before then that  required archaeologists to label and give proper contexts to monuments and artefacts. There was also a global movement to protect by law and provide resources and funds for monuments that were nationally important, but also those deemed significant to human civilization as a whole. Founded in 1945, has many responsibilities, one of the most important as far as archaeological conservation is concerned is the World Heritage List. The list began in 1975 as a recognition of globally important sites. The first 12 added on that first day included: L’Anse Aux Meadows in Canada, The Galapagos Islands, Quito in Ecuador, Krakow, and Mesa Verde National Park in the US. Today, there are over 1,000 cultural monuments and natural landscapes on this list. In the 21st century, it is common for countries to have laws in place to protect monuments, sites, and landscapes of cultural or historical importance and governmentestablished charities or government departments assigned to their management, upkeep or conservation. The threats to them and their conservation go beyond the issues of the 19th century (plunder and theft)
3. The word “indicators” in paragraph 2 is closest in meaning to _______.

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If you were going to choose a job that involves travel, what would be your first choice? There are many jobs available today that give people opportunities to travel. Although may traveling careers sound fantastic, they also have disadvantages.
Being an au pair is an excellent way to not only go to different countries, but to live in different places around the world and really get a feel for the culture. Au pairs lives with the families they are placed with and take of children. Many parents include au pairs in family events and vacations, so they experience many aspects of the new culture while on the job. However, many of the activities are centered around the children, so they may not get to experience many things that interest adults.
For people who want a bit more freedom working abroad, being an English teacher maybe a good choice. There are English teaching jobs in almost countries in the world. People teaching English in other countries often have a chance to travel on the weekends around the country. One drawback is that many teachers often wind up hanging out with other English teachers, and they don’t have time to learn the country’s language.
The nickname “roadie” implies that this job involves life on the road. Roadies are people who work and travel with bands and provide technical support. Roadies can be lighting and stage crew who set up the stage and break it down before and after events. They can also be technicians helping band members with their instruments. International tours take a band’s crew to cities around the world, often requiring air travel. However, the crew doesn’t get much time off, so they may travel to several countries without seeing much besides concert venues and hotels.
Similarly, flight attendants often travel to cities around the world, but they don’t see much besides the inside of airplanes and hotels. However, when they do have time off, they can often fly at no cost, and family member can sometimes fly free as well. Its is widely thought that a flight attendant job is
glamorous, but flight attendants must deal with travel hassles, as well as security issues.
All jobs gave advantages and disadvantages whether or not you travel for work, so if you have the travel bug, keep these jobs in mind for the future.

The word “glamorous” in paragraph 5 is closet in meaning to    .

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There have never been so many people living in cities in quake zones because the worse the damage can be from a big quake, bringing fires, tsunamis, and the loss of life, property, and maybe an entire city. We understand how earthquakes happen but not exactly where or when they will occur. Until recently, quakes seemed to occur at random. In Japan, government research is now showing that quakes can be predicted. At the Earthquake Research Institute, University of Tokyo, Koshun Yamaoka says earthquakes do follow a pattern—pressure builds in a zone and must be released. But a colleague, Naoyuki Kato, adds that laboratory experiments indicate that a fault slips a little before it breaks. If this is true, predictions can be made based on the detection of slips. Research in the U.S. may support Kato’s theory. In Parkfield, California earthquakes occur about every 22 years on the San Andreas fault. In the 1980s, scientists drilled into the fault and set up equipment to record activity to look for warning signs. When an earthquake hit again, it was years off schedule. At first the event seemed random but scientists drilled deeper. By 2005 they reached the bottom of the fault, two miles down, and found something. Data from two quakes reported in 2008 show there were two “slips’—places where the plates widened—before the fault line broke and the quakes occurred. We are learning more about these destructive events every day. In the future we may be able to track earthquakes and design an early-warning system. So if the next great earthquake does happen in Tokai, about 100 miles southwest of Tokyo, as some scientists think, the citizens of Tokai may have advance warning
3. The underlined word “it” in the passage refers to _____________

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Human beings are plagued by all kinds of diseases and millions of people die from them. Many of these diseases such as diabetes, polio, whooping cough and diphtheria can be fatal and in the past, people used to die from them. However, with modern technology and a lot of research, scientists and doctors have come up with various ways to cure these diseases, and consequently, many lives are saved. In doing the medical research, doctors have come face to face with many problems. One such problem is the opposition that comes from animal activists. They are against the inhuman treatment of animals. They argue that in conducting their medical research, doctors put animals through a very painful process and this should be stopped. According to the fiercest animal activists, nothing justifies the use of animals in medical experiments, even if lives might be saved. To get their message across, animal activists are even willing to resort to the use of violence. Many animal protection groups, like the Animal Liberation Front (ALF), have broken into laboratories illegally to ‘rescue’ animals. They take away whatever animals they can find and free them. These people also make their case by threatening the researchers. They vandalize medical equipment, and in the most serious cases, they even . In stealing the animals, the activists are actually hindering the progress of medicine. In many cases, the animals were part of research for the cure for various diseases and visual defects in babies. Cures for problems that people face, therefore, come slower and in the waiting period, more people die. Researchers have come up with many cures in the process of working with animals and on animals. Organ transplants are so common today, but we forget that they became only  possible after they were tested on animals. Doctors were able to come up with a cure for river blindness, a disease that affects millions of people in South America and Africa. These are only a few examples, and there are many more. In spite of what animal activists think, most researchers do not treat animals cruelly. In fact, mistreated animals which are in agony will affect the quality of research so that results obtained are not really reliable. Thus, researchers do try to treat animals as well as possible. In the long run, animal activists can cause serious damage to the future of medicine. With their persistent campaigning, much of the public supports their cause. People with AIDS or cancer need doctors to do research to save their lives, and often it is a case where animal research is crucial before any cure can be found  
4. Thanks to tests on animals, doctors succeeded in ____