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Just as optical fibers have transformed communication, they are also revolutionizing medicine. These ultra - thin, flxible fiers have opened a window into the living tissues of the body. By inserting optical fibers through natural openings or small incisions and the threading them along the body's established pathways, physicians can look into the lungs, intestines, heart and other areas that were formerly inaccessible to them. The basic fiber-optics system is called fiberscope, which consists of two bundles of fibers. One, the illuminating bundle, carries light to the tissues. It is coupled to a high-intensity light source. Light enters the cores of the high-purity silicon glass and travels along the fibers. A lens at the end of the bundle collects the light and focuses it into the other bundle, the imaging bundle. Each fibers in the bundle transmits only a tiny fraction of the total image. The reconstructed image can be viewed through an eyepiece or displayed on a television screen. During the last five years, improved methods of fabricating optical fibers have led to a reduction in fiberscope diameter and an increase in the number of fibers, which in turn has increased resolution. Optical fibers can also be used to deliver laser light. By use of laser beams, physicians can perform surgery inside the body, sometimes eliminating the need of invasive procedures in which healthy tissue must be cut through to reach the site of disease. Many of these procedures do not require anesthesia and can be performed in a physician's office. These techniques have reduced the risk and the cost of medical care.
4. The word "them" inparagraph 1, refers to: 

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The walnut tree produces wood that is used for countless purposes, and is considered the finest wood in the world. The wood is easy to work with, yet it is very hard and durable - and when it is polished, it produces a rich, dark luster. It also shrinks and swells less than any other wood, which makes it especially desirable for fine furniture, flooring, and even gun stocks. In fact, just about every part of the walnut is unusually hard and strong. The nut of the tree is encased inside a very hard shell, which itself is enclosed in a leathery outer covering called a husk. It requires real effort to break through those layers to get at the tasty meat inside. Yet every part of the walnut is useful to people. The outer husk produces a dark reddish stain that is hard to remove from the hands of the person who opens the nut, and this pigment is widely used in dyes and wood stains. The inner shell is used as an abrasive to clean jet engines. And the meat of the nut is extensively used in cooking, ice cream, flavourings - and just eaten raw. Walnut trees exude a chemical into the soil near their roots which can be poisonous to some trees and shrubs. Fruit trees, for example, will not survive if planted too close to a walnut. Many other plants, such as maple trees or ivy, are not affected by the walnut’s presence, and are well-suited to grow in its vicinity
3. As used in the passage, the underlined word "pigment” most nearly means ____

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College is a new and different experience for me. I’m away from home, so I have  many things to adjust to. Being on my own, talking with friendly people, and having Fridays off - these are just some things I like about college.  Living at college, first of all, gives me a sense of responsibility, of being on my own. My parents are not around to say, “No, you’re not going out tonight.” Or “Did you finish your homework?” Everything I do has to be my decision, and that gives me the responsibility of handling my own life. During the second week I was at college, I had to go out and look for a bank where I could open an account. Before that I looked in the phone book since I had no clue about any banks around here or where they were located. Someone told me to go to a bank named Continental Federal Savings. And I had to make my own decision - whether to have a checking or saving account and whether or not to get a card. I’m on my own to make my own decisions.  I also love to have Fridays off. I wouldn’t be able to deal with five days of classes in a row. I love to sleep in. One Thursday night, my roommates and I went to Georgetown. We got in rather early the next morning, and my roommates and I decided to sleep in, something I couldn’t do in high school.  I do like things about college - being on my own and having Fridays off, but this doesn’t mean I don’t think about things at home. Although I like college, I can still get homesick: New York is a pretty good place, too. 
3. The example of going to a bank in paragraph 2 shows the author

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Nowadays, dozens of interventions are known that extend the lifespan of various living organisms ranging from yeast to mammals. They include chemical compounds, genetic interventions, and diets. Some targets of these interventions have been discovered. However, there is still no clear understanding of the systemic molecular mechanisms leading to lifespan extension. A group of scientists from Skoltech, Moscow State University and Harvard University decided to fill this gap and identify crucial molecular processes associated with longevity. To do so, they looked at the effects of various lifespan-extending interventions on the activity of genes in a mouse, a commonly used model organism closely related to humans. “In our lab, we subjected mice of different sexes and ages to 8 longevity interventions and analyzed gene expression changes induced by these treatments. After aggregating our data with the datasets published by other groups, we obtained gene activity profiles of 17 interventions. Although in general the effects produced by individual treatments turned out to be rather specific, a certain group of genes changed its expression in a similar way in response to different lifespan-extending interventions,” says the first author of the study, Alexander Tyshkovskiy. The scientists then applied the discovered biomarkers to search for other interventions with the same effect on their activity and, therefore, high potential for lifespan extension "Currently, we are validating these hits by testing their effect on the mouse lifespan. We hope that our biomarkers will significantly facilitate the search for new longevity interventions and help improve the healthspan and lifespan in rodents and, in the long term, in humans," says Alexander. 
1. The passage mainly discusses _________

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Scientists believe that something very serious is happening to the Earth. It is becoming warmer. Scientists predict that there will be major changes in the climate during the 21st century. Coastal waters will have higher temperatures. This will have a serious effect on agriculture. Farmers will have trouble producing good crops. In warm regions, the weather will be too dry. The amount of water could decrease by 50 per cent. This would cause a large decrease in agricultural production. World temperatures could increase from 1.5 to 5.6 degrees Celsius by the middle of the 21st century. And the increase in temperature could be even greater in the Arctic and Antarctic regions. A rise in temperature could cause the great ice sheets to melt, which, in turn would raise the level of oceans by one to two meters. Many coastal cities would be underwater. Why is all this happening? The Earth and its atmosphere are kept warm by the Sun. The atmosphere lets most of the light from the Sun pass through to warm the Earth. The Earth is warmer by the sunlight and sends heat energy back into the atmosphere. Much of this energy escapes from the Earth’s atmosphere. However, some of it remains. Gases such as carbon dioxide, ozone and water vapor absorb this energy and create more heat. Then, this heat is sent back down to Earth, and the Earth becomes warmer. Recently, however, an increase of carbon dioxide in the atmosphere is causing serious problems. Too much carbon dioxide in the atmosphere prevents heat energy from escaping. Too much heat is sent back down to the Earth, and the amount of carbon dioxide in the atmosphere continues to increase. When oil, gas, and coal burn, they create large amounts of carbon dioxide. The destruction of rain forests that absorb carbon dioxide also helps to increase the amount of carbon dioxide in our atmosphere. Some scientists believe that the amount of carbon dioxide in the air will double by the late 2000s. Scientists call this warming of the Earth and its atmosphere “the greenhouse effect”. A greenhouse, made of glass and plastic, is a special place where plants are grown. The sunlight passes through the glass or plastic and warms the air inside. The heat inside escapes very slowly, so the greenhouse remains very warm. This is exactly what is happening on the Earth. Another reason why the Earth is growing warmer is because of the amount of ozone in our atmosphere. Ozone is a form of oxygen. In the upper atmosphere, very far from the Earth, a layer of ozone helps to protect the Earth from 95 percent of the harmful light that comes from the sun. If your skin receives too much of this light, you would develop skin cancer. We need the ozone layer to protect ourselves. But the ozone layer is in trouble. Scientists have observed that the ozone layer is becoming thin, and above Antarctica there is a hole. This allows too much of the sun’s dangerous light into our atmosphere and makes the Earth warmer. Scientists say we must start making changes and planning now. We need to continue to do research, so we can predict what will happen in the future. We must burn less coal, oil, and gas. Other scientists believe that the problem is not so serious. They think that the Earth is growing warmer naturally, that we don’t need to worry about it now, and that we should just get ready for life in the warmer climate. Most scientists agree that the causes of the world’s climate are very complicated. They say that we must continue to measure the amount of carbon dioxide and ozone in the atmosphere. Scientists also encourage people to learn about the changes that are occurring in the world and how we can all help protect our atmosphere  
2. A rise in temperature will be more remarkable ____.

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With 13,000 floral species and over 15,000 faunal species, three newly discovered big animal species, and a ratio of country/world species of 6.3%. Vietnam has enormous tourismparticularly ecotourism-potential. In fact, since 1986, when Renovation Reforms began the shift from a centrally planned to a socialist-oriented market, or multi-sectoral, economy, tourism has been an sector of primary concern to the government. In May 1995, the prime minister of Vietnam approved a master plan of tourism development for the period 1995- 2010. In February 1999, the state decree on tourism was part of the socio-economic development strategy for the period 2001-2010 approved at the IX National Congress of the Party: “Tourism development has become a spearhead economic industry indeed. It is necessary to improve the quality and effectiveness of tourism activities, bringing into full play the natural conditions, and cultural and historical tradition to meet the domestic and international demand for tourism and to catch up with tourism development in the region” (Document of the IX National Congress 2001). Tourism has so far brought great benefits to the economy, but it has also contributed to environmental degradation, especially biodiversity deterioration. Thus, the concept of “sustainable development”-development which meets the needs of the present without compromising the ability of future generations to meet their own needs - must be factored into tourism development. This consideration is reflected in the term “ecotourism,” which is referred to variously as ecological or environmental tourism, nature or green tourism, sustainable or responsible tourism. Ecotourism involves travel to relatively undisturbed natural areas with the specific object of studying, admiring, and enjoying scenery, plants, and animals, as well as any cultural features found in these areas. It is distinguished from mass or resort tourism by its lower impact on the environment, lower infrastructure requirements, and its role in educating tourists about natural environments and cultural values. Fully aware of its significance, the government of Vietnam has prioritized ecotourism in its strategy for tourism development to ensure both sustainability and economic benefits. Though ecotourism in Vietnam is at a beginning stage of development, it is expected to grow strongly through support from government and international organizations.  
2. When has tourism officially contributed to socio-economic development?

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Long life expectancy can be attributed to a person’s diet - a healthy, balanced diet has been proven to improve longevity. Experts recommend eating at least five portions of a variety of fruit and vegetables every day, basing meals on higher starchy foods like potatoes, bread and rice, having some dairy or dairy alternatives, eating some protein, choosing unsaturated oils and spreads, and drinking plenty of fluids. But new research, published this week, has found the times of day a person eats holds the most benefits. Dr Mark Mattson, a professor of neuroscience at John Hopkins University School of Medicine, in the US, has said “intermittent fasting could be part of a healthy lifestyle.” Intermittent fasting diets usually involve daily time-restricted feeding, which narrows eating times to six to eight hours per day and so-called 5:2 intermittent fasting, in which people limit themselves to one moderate-sized meal two days each week. A range of human and animal studies have shown that alternating between times of fasting and eating supports cellular health, probably by triggering an age-old adaptation to periods of food scarcity called metabolic switching. Such a switch occurs when cells use up their stores of rapidly accessible, sugar-based fuel, and begin converting fat into energy in a slower metabolic process. Dr Mattson says studies have shown that this switch improves blood sugar regulation, increases resistance to stress and suppresses inflammation. Because most Americans eat three meals plus snacks each day, they do not experience the switch, or the suggested benefits. In an article in the New England Journal of Medicine, Dr Mattson said four studies in both animals and people found intermittent fasting also decreased blood pressure, blood lipid levels and resting heart rates.  
1. Which best serves as the title for the passage? 

Find synonym:
I was shocked to find out my boyfriend had cheated on me.

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Taking piano lessons and solving math puzzles on a computer significantly improve specific math skills of elementary schoolchildren, according to a new study. The results, (1)______ were published in the journal Neurological Research, are the latest in a series that links musical training to the development of higher brain functions. Researchers worked with 135 second-grade students at a school in Los Angeles after (2)______ a pilot study with 102 students. Children that were given four months of piano training as well as time playing (3)______ newly designed computer software scored 27 percent higher on math and fraction tests than other children. Piano instruction is thought to enhance the brain's "hard wiring" for spatial-temporal reasoning, or the ability to visualise and transform objects in space and time, says Professor Gordon Shaw, who led the study. At the same time, the computer game allows children to solve geometric and math puzzles that boost their ability to (4)______ shapes in their mind. The findings are significant (5)______ a grasp of proportional math and fractions is a prerequisite to math at higher levels, and children who do not master these areas of math cannot understand more advanced math that is critical to high-tech fields.

Find mistake:
Her uncle lived in Barcelona for several years, which he taught Spanish.

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The issue of equality for women in British society first attracted national attention in the early 20th century, when the suffragettes won for women the right to vote. In the 1960s feminism became the subject of intense debate when the women's liberation movement encouraged women to reject their traditional supporting role and to demand the equal right with men in areas such as employment and play. Since then, the gender gap between the sexes has been reduced. The Equal Pay Act of 1970, for instance, made it illegal for woman to be paid less than men for doing the same work, and in 1975 the Sex Discrimination Act aimed to prevent either sex having an unfair advantage when applying forjobs. In the same year the Equal Opportunities Commission was set up to help people claim their rights to equal treatment and to publish research and statistics to show where improvements in opportunities for women need to be made. Women now have much better employment opportunities, though they still tend to get less well-paid jobs than men, and very few are appointed to top jobs in industry. In the US the movement that is often called the"first wave of feminism"began in the 1800s. Susan B. Anthony worked for the right to vote, Margaret Sanger wanted to provide women with the means of contraception so that they could decide whether or not to have children, and Elizabeth Blackwell, who had to fight for the chance to become a doctor, wanted to have greater opportunities to study. Many feminists were interested in other social issues. The second wave of feminism began in 1960s. Women like Betty Friedan and Gloria Steinem became associated with the fight to get equal rights and opportunities for women under law. An important issue was the Equal Rights Amendment (ERA), which was intended to change the Constitution. Although the ERA was not passed, there was progress in other areas. It became illegal for employers, schools, clubs, etc... to discriminate against women. But women still find it hard to advance beyond a certain point in their career, the so-called glass ceiling that prevents them from having high level jobs. Many women also face the problem of the second shift, i.e. the household chores. In the 1980s, feminism became less popular in the US and there was less interest in solving the remaining problems, such as the fact that most women still earn much less than men. Although there is still discrimination, the principle that it should not exist is widely accepted.
3. Susan B. Anthony, Margaret Sanger, and Elizabeth Blackwell are mentioned as .......

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At its narrowest point, Vietnam is only 30 miles (48 kilometers) wide. Two of Vietnam’s largest rivers, the Mekong in the south and the Red in the north, end at the South China Sea in huge swampy plains called (1)________ . These regions are home to most of the country’s people and provide (2)________ ground to grow rice and many other crops. Vietnam’s mountainous terrain, forests, wetlands, and long coastline contain many different habitats that support a great (3)________ of wildlife. Some 270 types of mammals, 180 reptiles, 80 amphibians, and 800 bird species reside in Vietnam Many rare and unusual animals live in Vietnam, (4)________ giant catfish, Indochinese tigers, Saola antelopes, and Sumatran rhinos. The government has set up 30 parks and reserves to protect its animals, but their survival is (5) ________doubt because much of their habitat has been cleared for lumber or to grow crops

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Jupiter is the largest and most massive planet and is fifth in order of distance from the sun. It is well placed for observation for several months in every year and on average is the brightest of the planets apart from Venus, though for relatively brief periods Mars may outshine it. Jupiter’s less than 10 hour rotation period gives it the shortest day in the solar system in so far as the principal planets are concerned. There are no true seasons on Jupiter because the axial inclination to the perpendicular of the orbital plane is only just over 3°-less than that for any other planet. The most famous mark on Jupiter is the Great Red Spot. It has shown variations in both intensity and color, and at times it has been invisible, but it always returns after a few years. At its greatest extent it may be 40,000 kilometers long and 14,000 kilometers wide, so its surface area is greater than that of Earth. Though the latitude of the Red Spot varies little, it drifts about in longitude. Over the past century the total longitudinal drift has amounted to approximately 1200°. The latitude is generally very close to – 22°. It was once thought that the Red Spot might be a solid or semisolid body floating in Jupiter’s outer gas. However, the Pioneer and Voyager results have refuted that idea and proven the Red Spot to be a phenomenon of Jovian meteorology. Its longevity may well due to its exceptional size, but there are signs that it is decreasing in size, and it may not be permanent. Several smaller red spots have been seen occasionally but have not lasted.
3. According to the passage, the Great Red Spot________

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The music club/ be/ make/ so/ much noise/ that/ the residents/ require/ them/ turn/ the music/ down.

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Herman Melville, an American author best known today for his novel Moby Dick, was actually more popular during his lifetime for some of his other works. He traveled extensively and used the knowledge gained during his travels as the basis for his early novels. In 1837, at the age of eighteen, Melville signed as a cabin boy on a merchant ship that was to sail from his Massachusetts home to Liverpool, England. His experiences on this trip served as a basis for the novel Redburn (1849). In 1841, Melville set out on a whaling ship headed for the South Seas. After jumping ship in Tahiti, he wandered around the islands of Tahiti and Moorea.This South Sea island sojourn was a backdrop to the novel Omoo (1847). After three years awayfrom home, Melville joined up with a U.S. naval frigate that was returning to the eastern United States around Cape Horn. The novel White Jacket (1850) describes this lengthy voyage as a navy seaman. With the publication of these early adventure novels, Melville developed a strong and loyal following among readers eager for his tales of exotic places and situations. However, in 1851, with the publication of Moby Dick, Melville's popularity started to diminish. Moby Dick, on one level the saga of the hunt for the great white whale, was also a heavily symbolic allegory of the heroic struggle of humanity against the universe. The public was not ready for Melville's literary metamorphosis from romantic adventure to philosophical symbolism. It is ironic that the novel that served to diminish Melville's popularity during his lifetime is the one for which he is best known today.
4. The word "basis" in paragraph 1 is closest in meaning to: 

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Russia offers to establish an organization with the participation of Russia, the US, EU  states and other countries in order to resolve the issues in the Persian Gulf, Russian President Vladimir Putin stressed on Thursday during the plenary session of the Valdai Discussion Club.  "I would like to remind you that following this logic, Russia has come up with the concept of ensuring collective security in the Persian Gulf in July of this year. I think that taking into account the volatile and unpredictable situation in the region, the idea remains topical. We offer to put aside our differences and mutual claims and to establish an organization for security and cooperation in the region basically from scratch, which would include the Gulf States and which could involve Russia, China, the US, the EU, India and other interested states as observers," he said.  On July 23, the Russian Foreign Ministry introduced a concept of collective security in the Persian Gulf region. The concept includes forming an initiative group to organize an international conference on security and cooperation in the Persian Gulf area, which would lead to the establishment of an organization for security and cooperation in the region. Besides, Moscow offered to establish demilitarized zones in the region, abandon permanent deployment of units of non-regional states and establish military hotlines. Earlier, during a joint press conference on the outcomes of the talks with Russian Foreign Minister Sergey Lavrov, Iranian top diplomat Mohammad Javad Zarif welcomed the Russian initiative. He added that Iran offers to create a coalition on security in the Persian Gulf, including Iraq, Saudi Arabia, Bahrain, the United Arab Emirates, Qatar, Oman and Kuwait under the auspices of the UN. 
4. According to paragraph 3, what is NOT the reaction of other countries toward the plan?

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Thirty years after ghostwriting Donald Trump’s The Art of the Deal, Tony Schwartz described the experience as like putting lipstick on a pig. He felt a “deep sense of remorse” at helping bring the man who would become president gain wider attention. This week, the writer Natalie Beach joined the grand tradition of ghostwriters speaking out about their subjects, with a deeply intimate essay in the Cut laying out how she used to ghost everything for her former friend and controversial “influencer” Caroline Calloway: from Instagram captions to the aborted book that once attracted a $375,000 (£300,000) publishing deal, until their relationship broke down irretrievably. Beach’s account says that after the pair put the book proposal together, the influencer felt unable to write it. Beach says she “bought us time with the publishers by writing a quarter of the manuscript by myself”. As a ghostwriter himself, Crofts questions the ethics of speaking out about his subjects’ lives. “I do think Tony Schwartz shouldn’t have come out and said anything about Trump, because you’ve taken the money. It’s like a lawyer: if you find that the person you’re representing is a murderer you can’t then go around bewailing the fact you defended them – that was your job,” he said. “But I think he made Trump, I don’t think Trump would be president if he hadn’t written that book for him, because he’d never have got The Apprentice without the book, and the presidency without The Apprentice. So it must be weighing heavily on his conscience.”  Ghostwriters must be good at several things – being amenable to being steered by a subject, while also being firm enough to guide them away from tangents and uninteresting details. But the most important thing in ghostwriting, says Crofts, is absence of ego. “Which is maybe what went wrong [with Calloway] – Natalie isn’t a born ghost, she’s a writer herself. She was really young and well out of her depth, completely swamped by this girl’s flamboyance,” he says. “Ghostwriters do attract a lot of fantasists and people who have ideas way above the likelihood of success. They always think their story is fantastically interesting and going to be a bestseller. You’re always dealing with people with larger-than-life egos, so there’s always a danger you’re going to run up against someone who is impossible to manage.”  
1. Which best serves as the title for the passage?

Find synonym:
In the past, a lot of countries denied having contributed to global warming

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Parents in most cases want the best for their children, and to ensure this, they are  pushed to actively engage in their children’s lives, to ensure that they are making the right choices. Some parents, however, go to the extent of wanting to have the upper hand even when it comes to taking major decisions, such as choosing a career.  Local comedian and actor, Michael Sengazi, was obliged by his parents to pursue a career in law, a path he followed when he joined University of Kigali, but deep down he knew this wasn’t his dream career. This is why after graduating he chose to follow his passion —comedy. His parents failed to understand how a qualified lawyer could decide to go for comedy because they didn’t see it as a ‘well-paying job’. He had a challenge of convincing them to bless his journey. “So, I asked them to give me one year to try and see if comedy would work out for me. I worked hard and my parents realised that I could achieve big things, and they gave me the freedom to pursue the career.”  Bienvenue Muragwa, a career consultant at The Southern New Hampshire University based in Rwanda, says that parents are only allowed to guide the child during the career guidance process, but not take the final decision. “Parents are not allowed to choose or take the final decision for their children as the performance of the student is the assessing parameter of the career to be pursued,” he explains.  Shalom Azabe, a graduate in general counselling at Kampala Christian University, says in most African countries, not only Rwanda, children are overly dependent on their parents, yet this shouldn’t be the case. She recommends picking a leaf from westerners who endeavour to learn their children’s interests, something she says aides them in career guidance for the child. “Normally, a child starts to demonstrate a choice in career at 14 years of age. This is when parents need to sit down and make analysis that would help them guide their child in choosing the fitting option to undertake. This is in fact considered as overprotection as parents want to exercise their authority on their kids unwillingly, yet this affects them psychologically, and when the kid later on fails, they encounter a regret of pursuing studies that were not their choice in the first place,” Azabe said.
4. The word “parameter” in paragraph 3 can be replaced by_______

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:
A massage is relaxing, and makes you feel great, but did you know that it's also good for you? That's what doctors are now saying. Massage relieves pain and anxiety, eases depression and speeds up recovery from medical problems.
Research has shown that people of all ages benefit from touch. Premature infants who are held develop faster than those left alone, and healthy babies who get a lot of physical contact cry less and sleep better. Researchers are not sure why this occurs but they have also found out that touch can slow heart rate, lower blood pressure and increase levels of seratonin, the brain chemical that is linked to well-being. It also decreases levels of the stress hormone cortisol, and this in turn increases your resistance to illness.
Massage also speeds up healing. Bone-marrow transplant patients who were given massages had better neurological function than those who weren't. Furthermore, massage reduced pain by 37% in patients with chronic muscle aches.
Giving someone a massage may be as good as getting one. A study conducted by the university of Miami found that mothers suffering from depression felt better after massaging their infants. In that same study, elderly volunteers who massaged infants reported feeling less anxious and depressed.
It even works when you do it yourself; 43% of headache sufferers reported getting relief after massaging their temples and neck and smokers who were taught self-massage while trying to quit felt less anxiety and smoked less.

What did the study conducted in Miami show?

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:
Pollution is a threat to many species on Earth, but sometimes it can cause species to thrive. Such is the case with Pfiesteria piscicida. A one-celled creature called a dinoflagellate, Pfiesteria inhabits warm coastal areas and river mouths, especially along the eastern United States. Although scientists have found evidence of Pfiesteria in 3,000-year-old sea floor sediments and dinoflagellates are thought to be one of the oldest life forms on earth, few people took notice of Pfiesteria.
Lately, however, blooms – or huge, dense populations – of Pfiesteria are appearing in coastal waters, and in such large concentrations the dinoflagellates become ruthless killers. The blooms emit powerful toxins that weaken and entrap fish that swim into the area. The toxins eventually cause the fish to develop large bleeding sores through which the tiny creatures attack, feasting on blood and flesh. Often the damage is astounding. During a 1991 fish kill, which was blamed on Pfiesteria on North Carolina’s Neuse River, nearly one billion fish died and bulldozers had to be brought in to clear the remains from the river. Of course, such events can have a devastating effect on commercially important fish, but that is just one way that Pfiesteria causes problems. The toxins it emits affect human skin in much the same way as they affect fish skin. Additionally, fisherman and others who have spent time near Pfiesteria blooms report that the toxins seem to get into the air, where once inhaled they affect the nervous system, causing severe headaches, blurred vision, nausea, breathing difficulty, short-term memory loss and even cognitive impairment.
For a while, it seemed that deadly Pfiesteria blooms were a threat only to North Carolina waters, but the problem seems to be spreading. More and more, conditions along the east coast seem to be favorable for Pfiesteria. Researchers suspect that pollutants such as animal waste from livestock operations, fertilizers washed from farmlands and waste water from mining operations have probably all combined to promote the growth of Pfiesteria in coastal waters.

What is especially worrying about Pfiesteria blooms?