Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
In young language learners, there is a critical period of time beyond which it becomes increasingly difficult to acquire a language. Children generally attain proficiency in their first language by the age of five and continue in a state of relative linguistic plasticity until puberty. [A] Neurolinguistic research has singled out the lateralization of the brain as the reason for this dramatic change from fluidity to rigidity in language function. Lateralization is the process by which the brain hemispheres become dominant for different tasks. The right hemisphere of the brain controls emotions and social functions, whereas the left hemisphere regulates the control of analytical functions, intelligence, and logic. [B] For the majority of adults, language functions are dominant on the left side of the brain. [C] Numerous studies have demonstrated that it is nearly impossible to attain a nativelike accent in a second language, though some adults have overcome the odds, after lateralization is complete. [D]
Cognitive development also affects language acquisition, but in this case adult learners may have some advantages over child learners. Small children tend to have a very concrete, here- and-now view of the world around them, but at puberty, about the time that lateralization is complete, people become capable of abstract thinking, which is particularly useful for language. Generally speaking, adults can profit from grammatical explanations, whereas children cannot. This is evidenced by the fact that children are rather unreceptive to correction of grammatical features and instead tend to focus on the meaning of  an utterance rather than its form. However, language learning theory suggests that for both adults and children, optimal language acquisition occurs in a meaning centered context. Though children have the edge over adult language learners with respect to attaining a nativelike pronunciation, adults clearly have an intellectual advantage which greatly facilitates language learning.

What is stated in the passage about the achievement of an accent like a native’s by an adult?

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The increase in international business and in foreign investment has created a need for executives with knowledge of foreign languages and skills in cross-culture communication. Americans, however, have not been well trained in either area and, consequently, have not enjoyed the same level of success in negotiation in an international arena as have their foreign counterpart.
Negotiating is the process of communicating back and forth for the purpose of reaching an agreement. It involves persuasion and compromise, but in order to participate in either one, the negotiators must understand the ways in which people are persuaded and how compromise is reached within the culture of the negotiation.
In many international business negotiations abroad, Americans are perceived as wealthy and impersonal. It often appears to the foreign negotiator that the American represents a large multimillion- dollar corporation that can afford to pay the price without bargaining further. The American negotiator’s role becomes that of an impersonal purveyor of information and cash, an image that succeeds only in undermining the negotiation.
In studies of American negotiators abroad, several traits have been indentified that may serve to confirm this stereotypical perception, while subverting the negotiator's position. Two traits in particular that cause cross-culture misunderstanding are directness and impatience on the part of American negotiator. Furthermore, American negotiators often insist on realizing short-term goals. Foreign negotiators, on the other hand, may value the relationship established between negotiators and may be willing to invest time in it for long-term benefits. In order to solidify the relationship, they may opt for indirect interactions without regard for the time involved in getting to know the other negotiator.
Clearly, perceptions and differences in values affect the outcomes of negotiations and the success of negotiators. For Americans to play a more effective role in international business negotiations, they must put forth more effort to improve cross-cultural understanding.

It can be referred from paragraph 1 that ..................

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Welcome to the Netherlands, a tiny country that only extends, at its broadest, 312 km north to  south, and 264 km east to west - (1) ......... the land area increases slightly each year as a result of continuous land reclamation and drainage. With a lot of heart and much to offer, ‘Holland,’ as it is (2).......known to most of us abroad - a name stemming from its once most prominent provinces - has more  going  on  per  kilometer  than  most  countries,  and  more  English-speaking  natives.  You’ll  be impressed by its (3).....cities and charmed by its countryside and villages, full of contrasts. From the exciting variety on offer, you could choose a romantic canal boat tour in Amsterdam, a Royal Tour by coach in The Hague, or a hydrofoil tour around the biggest harbour in the world - Rotterdam. In season you could visit the dazzling bulb fields, enjoy a full day on a boat, or take a bike tour through the pancake-flat countryside spiced with windmills. The possibilities are countless and the nationwide tourist office is on hand to give you information and help you (4)...... reservations.  You’ll  have (5)........language problems here, as the Dutch are true linguists and English is spoken here almost universally.
(3)...........................

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Geothermal energy is natural heat from the interior of the Earth that is converted to heat buildings and generate electricity. The idea of harnessing Earth’s internal heat is not new. As early as 1904 , geothermal power was used in Italy . Today, Earth’s natural internal heat is being used to generate electricity in 21 countries , including Russia, Japan, New Zealand, Iceland, Mexico, Ethiopia, Guatemala, EI Salvador, the Philippines, and the United States .Total worldwide production is approaching 9,000 MW (equivalent to nine large modern coal-burning or nuclear power plants)-double the amount in 1980 .Some 40 million people today receive their electricity from geothermal energy at a cost competitive with that of other energy sources. In EI Salvador , geothermal energy is supplying 30% of the total electric energy used.
However, at the global level, geothermal energy supplies less than 0,15%of the total energy supply.
Geothermal energy may be considered a nonrenewable energy source when rates of extraction are greater than rates of natural replenishment. However, geothermal energy has its origin in the natural heat production within Earth , and only a small fraction of the vast total resource base is being utilized today. Although most geothermal energy production involves the tapping of high heat sources, people are also using the low-temperature geothermal energy of groundwater in some applications.

Geothermal Systems
The average heat flow from the interior of the Earth is very low, about 0,06% W/m2.This amount is trivial compared with the 177 W/m2from solar heat at the surface in the United States. However, in some areas, heat flow is sufficiently high to be useful for producing energy . For the most part, areas of high heat flow are associated with plate tectonic boundaries. Oceanic ridge systems (divergent plate boundaries) and areas where mountains are being uplifted and volcanic island arcs are forming (convergent plate boundaries) are areas where this natural heat flow is anomalously high. One such region is located in the western, United States, where recent tectonic and volcanic activity has occurred.
On the basis of geological criteria, several types of hot geothermal systems (with temperatures greater than about 800C , or 1760F)have been defined, and the resource base is larger than that of fossil fuels and nuclear energy combined. A common system for energy development is hydrothermal convection, characterized by the circulation of steam and / or hot water that transfers heat from depths to the surface.

The attraction of gold is as old as history. Since ancient times, gold has been the object of dreams and obsessions. Western literature is full of characters who kill for gold or hoard it, from King Midas in the ancient Greek myths, to Fagin in Dickens' Oliver Twist. These characters go to evil extremes to get or keep their gold and they get the punishment they deserve. Most people would not be willing to go to such extremes, of course, but they would not question the assumption that gold has lasting value above and beyond any local currency. Societies change over time, customs and currencies evolve, but gold remains. A wedding ring, for example, must be gold, and so should any serious gift of jewelry. In fact, giving and wearing gold is still a mark of prestige in our post-industrial society, though gold is no longer valued as it used to be thousands of years ago.
Why is gold so valuable? True, it is shiny, durable, and rare, but it is far less useful than many other minerals or metals. It is also not like stock in a company, where the value of the stock depends on the performance of the company. Gold, on the contrary, like any currency, is valuable precisely because people believe it is valuable. That is, if people were willing to accept seashells for their labor and could use them to pay for food, fuel, and other commodities, then seashells would become a valuable currency. Thus, the value of gold depends on the collective belief that gold will continue to be valuable. As long as demand for gold remains steady, the price will hold steady; if demand is high, it will continue to increase in value. But if people should someday lose faith in gold, the price of gold could fall sharply.
Another factor that has affected the price of gold has been the increasing difficulty in acquiring it. Today, most of the gold left in the grounds is in microscopic pieces mixed with rock. To get it, miners must dig up tons and tons of rock, and then spray it with chemicals to separate out the gold. For one ounce of gold - a wedding ring, for example - the mine processes about 30 tons of rock. This is already a costly operation. But there are also hidden social and environmental costs. The mining and processing of gold is ruinous to the environment and to the health of people living nearby. Most of these mines are in poor regions where the people have had little voice in whether there should be mines and how the mines should be run. The large multinational mining companies simply bought the land and opened the mines. However, as people and governments begin to realize the extent of the damage caused by the mines, the situation might change.
Indeed, if the mining companies ever have to pay the full environmental and social costs of mining gold, the price of gold is likely to climb yet higher.

The word " ruinous " is closest meaning to .............

Choose the item among A, B, C or D that best answers the question about the passage:

"When Franklin Roosevelt was elected President of the United States in 1932. not only the United States but also the rest of the world was in the throes of an economic depression. Following the termination of World War I, Britain and the United States at first experienced a boom in industry. Called the Roaring Twenties, the 1920s ushered in a number of things - prosperity, greater equality for women in the work world, rising consumption, and easy credit. The Outlook for American business was rosy.
 October 1929 was a month that had catastrophic economic reverberation worldwide. The American stock market witnessed the “Great Crash,” as it is called, and the temporary boom in the American economy came to a standstill. Stock prices sank, and panic spread. The ensuing unemployment figure soared to 12 million by 1932.
 Roosevelt was elected because he promised a “New Deal” to lift the United States out of the doldrums of the depression. Following the principles advocated to Keynes, a British economist, Roosevelt mustered the spending capacities of the federal government to provide welfare, work, and agricultural aid to the millions of down-and-out Americans. Roosevelt succeeded in dragging the nation out of the Depression before the outbreak of World War II."

5. Roosevelt’s “New Deal” advocated ……. .

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Twenty-five students from Walling School are currently living in France. They are there for three months as part of a living-abroad project. The 16- and 17-year-old students are living with French families and attending a French school. Most of the students have taken French language classes for 3 or 4 years and are finally getting an opportunity to use their French.
Not only are students learning a new language, but they are learning about a new culture, too. Students have been particularly surprised about the French attitude towards food. “They won’t leave anything on their plate,” says Vanessa Athol. “They aren’t wasteful at all.” Vanessa has vowed to be more careful with waste when returning to the United States.
The group’s chaperone, Mrs. Smith, has been pleased with the students’ acquisition of language. “Even the most timid are trying their best to speak. The students are learning a lot. I’m very impressed,” she said. Mrs. Smith added that she thinks living with a French family makes a difference because students are forced to speak French. “We are all very grateful to the French families who are hosting us.”
The French families are happy to have the students, as they are getting to leam about American culture. Both groups will be celebrating the exchange at a large potluck dinner at the end of the stay. There will be a slide show of memories and the students will speak about their experiences. Currently, the American students are periodically posting pictures and student essays on the Walling School website. “Living in France is an experience I’ll never forget,” writes student Tina Davis. “I know I’ll want to eat these croissants and this Camembert for the rest of my life!”

Which title would be the most suitable for this article?

It was the first photograph that I had ever seen, and it fascinated me. I can remember holding it at every angle in order to catch the flickering light from the oil lamp on the dresser. The man in the photograph was unsmiling, but his eyes were kind. I had never met him, but I felt that I knew him. One evening when I was looking at the photograph, as I always did before I went to sleep, I noticed a shadow across the man’s thin face. I moved the photograph so that the shadow lay perfectly around his hollow cheecks. How different he looked!
That night I could not sleep, thinking about the letter that I would write. First, I would tell him that I was eleven years old, and that if he had a little girl my age, she could write to me instead of him. I knew that he was a very busy man. Then I would explain to him the real purpose of my letter. I would tell him how wonderful he looked with the shadow that I had seen across his photograph, and I would most carefully suggest that he grow whiskers.
Four months later when I met him at the train station near my home in Westfield, New York, he was wearing a full beard. He was so much taller than I had imagined from my tiny photograph.
“Ladies and gentlemen,” he said, “I have no speech to make and no time to make it in. I appear before you that I may see you and that you may see me.” Then he picked me right up and kissed me on both cheeks. The whiskers scratched. “Do you think I look better, my little friend?” he asked me.
My name is Grace Bedell, and the man in the photograph was Abraham Lincoln.

From this passage, it may be inferred that...........

Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage:

"Quite apart from the economic similarity between present-day automation and the mechanization which has been proceeding for centuries, it must also be stressed that even in the United States automation is by no means the only factor (1)….. people from existing jobs.
 The increasing number of unneeded workers in (2)…. years has been the result of much more simple and old-fashioned influences: farm labourers have been (3)…. out of work by bigger tractors, miners by the cheapness of oil, and railwaymen by better roads.
 It is quite wrong, therefore, to think of automation as some new monster whose arrival (4)…. the existence of employment in the same way that the arrival of myxomatosis threatened the existence of the rabbit. Automation is one (5)….. of technological change, which itself is only one of the several changes (changes in tastes, changes in social patterns, changes in organization) which (6)…. in certain jobs disappearing and certain skills ceasing to be required. And even in America, which has a level of technology and output per (7)…. much in (8)….. of Britain’s, there is no (9)…. that the (10)….  of change is actually speeding up.
 Nevertheless changes in the amount of labour needed to produce a certain output are proceeding fairly rapidly in America - and in other countries - and my proceed more rapidly in future. Indeed it is one of the main objects of economic policy."

9. there is no (9)…. 

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Theresa May, the second female Britain’s prime minister following Margaret Thatcher, revealed in 2013 that she had been given a diagnosis of Type 1 diabetes, a condition that requires daily insulin injections. Asked later how she felt about the diagnosis, she said her approach to it was the same as toward everything in her life: “Just get on and deal with it.” That kind of steeliness brought her to center stage in the aftermath of Britain’s vote to leave the European Union and the feuding that erupted in the Conservative Party over who would succeed David Cameron.
Ms” May, 59 years old, is the country’s longest-serving home secretary in half a century, with a reputation for seriousness, hard work and above all, determination. She is one of a growing number of women in traditionally male-dominated British politics rising to the upper position of leadership.
Bom in 1956, Ms. May grew up mainly in Oxford shire, an only child who was first drawn to the Conservative Party at age 12. As a conscientious student, she never rebelled against her religious upbringing and remains a regular churchgoer. Tellingly, her sports hero was Geoffrey Boycott, a solid, stubborn cricketer who specialized in playing the long game.
Like many other Britain’s prime minister including Tony Blair, Sir Robert Peel and Margaret Thatcher, she won a place at Oxford. But while almost every other political leader got there by way of Eton College and joined Oxford’s hedonistic Bullingdon Club, she attended a state secondary school and had a more sedate university career. After unsuccessful attempts to be elected to the House of Commons in 1992 and 1994, she finally became an MP in 1997 general election.
May is known for a love of fashion and in particular distinctive shoes. She even wore leopard-print shoes to her final Cabinet meeting as Home Secretary in early 2016. However, she has been quite critical of the media focusing on her fashion instead of her achievement as a politician. May also describes cooking and walking as primary hobbies, and if someone is raising questions about why walking can be classified as a hobby, she elaborates in a column for Balance magazine, in which she wrote of her battle with diabetes.

She first became a member of parliament in ..................

Choose the word or phrase ( A, B, C or D ) that best fits the blank space in the following passage.

What do you do well? What do you enjoy doing? Your answers to these two questions will help you identify your (1)_____. An employer will consider you seriously for a (2)___ when you can show them that you know who you are, what you can offer and which you have studied. Sometimes it is difficult to know what your weaknesses are. Clearly not everyone is equally good (3) ___ everything. You may need to improve yourself and so (4) ___courses in that field could turn a weakness into strength.

You will need to (5) ___some time on your self-assessment. Your honesty and the desire for self-improvement will lead to success in getting the right job. Explore the following seven areas to start to get to know yourself: your aptitude, your skills, your personality, the level of responsibility you feel comfortable with, your interests and your needs.

(4)_____

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Neil Armstrong started flying at an early age. He became interested in airplanes at the age of 2. At 15, he took flying lessons. He got a license to fly at 16. He learned how to fly before he learned how to drive a car. At university, he studied aeronautical engineering. This is the study of designing and making aircraft.
After Armstrong became an astronaut in 1962, he was trained for 4 years for the Apollo program. The Apollo mission was to put a man on the moon in ten years. On July 16, 1969, the Apollo 11 landed on the moon. Because Armstrong was the leader, he became the first man to step on the moon. He said, "This is one small step for a man, one giant leap for mankind." He and his fellow astronaut, Buzz Aldrin, walked on the moon for two and a half hours. They collected rocks and did some experiments.

According to paragraph 2, which of the following is true about Armstrong's training as an astronaut?

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The ocean bottom - a region nearly 2.5 times greater than the total land area of Earth - is a vast frontier that even today is largely unexplored and uncharted. Until about a century ago, the deep-ocean floor was completely inaccessible, hidden beneath waters averaging over 3,600 meters deep. Totally without light and subjected to intense pressures hundreds of times greater than at the Earth's surface, the deep-ocean bottom is a hostile environment to humans, in some ways as forbidding and remote as the void of outer space.
Although researchers have taken samples of deep-ocean rocks and sediments for over a century, the first detailed global investigation of the ocean bottom did not actually start until 1968, with the beginning ofthe National Science Foundation's Deep Sea Drilling Project (DSDP). Using techniques first developed for the offshore oil and gas industry, the DSDP's drill ship, the Glomar Challenger, was able to maintain a steady position on the ocean's surface and drill in very deep waters, extracting samples of sediments and rock from the ocean floor.
The Glomar Challenger completed 96 voyages in a 15-year research program that ended in November 1983. During this time, the vessel logged 600,000 kilometers and took almost 20,000 core samples of seabed sediments and rocks at 624 drilling sites around the world. The Glomar Challenger's core samples have allowed geologists to reconstruct what the planet looked like hundreds of millions of years ago and to calculate what it will probably look like millions of years in the future. Today, largely on the strength of evidence gathered during the Glomar Challenger's voyages, nearly all earth scientists agree on the theories of plate tectonics and continental drift that explain many of the geological processes that shape the Earth.
The cores of sediment drilled by the Glomar Challenger have also yielded information critical to understanding the world's past climates. Deep-ocean sediments provide a climatic record stretching back hundreds of millions of years, because they are largely isolated from the mechanical erosion and the intense chemical and biological activity that rapidly destroy much land-based evidence of past climates. This record has already provided insights into the patterns and causes of past climatic change - information that may be used to predict future climates.

Which of the following is true of the Glomar Challenger?

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The nuclear family, consisting of a mother, father, and their children, may be more an American ideal than an American reality. Of course, the so-called traditional American family was always more varied than we had been led to believe, reflecting the very different racial, ethnic, class, and religious customs among different American groups.
The most recent government statistics reveal that only about one third of all current American families  fit the traditional mold and another third consists of married couples who either have no children or have none still living at home. Of the final one third, about 20 percent of the total number of American households are single people, usually women over sixty-five years of age. A small percentage, about 3 percent of the total, consists of unmarried people who choose to live together; and the rest, about 7 percent are single, usually divorced parents, with at least one child.
Today, these varied family types are typical, and therefore, normal. Apparently, many Americans are achieving supportive relationships in family forms other than the traditional one.

With what topic is the passage mainly concerned?

Bees, classified into over 10,000 species, are insects found in almost every part of the world except the northernmost and southernmost regions. One commonly known species is the honeybee, the only bee that produces honey and wax. Humans use the wax in making candles, lipsticks, and other products, and they use the honey as a substance that people eat to maintain life and growth. While gathering the nectar and pollen with which they make honey, bees are simultaneously helping to fertilize the flowers on which they land. Many fruits and vegetables would not survive if bees did not carry the pollen from blossom to blossom.
Bees live in a structured environment and social structure within a hive, which is a nest with storage space for the honey. The different types of bees each perform a unique function. The worker bee carries nectar to hive in a special stomach called a honey stomach. Other workers make beeswax and shape it into a honeycomb, which is a waterproof mass of six-sided compartments, or cells. The queen lays eggs in completed cells. As the workers build more cells, the queen lays more eggs.
All workers, like the queen, are female, but the workers are smaller than the queen. The male honeybees are called drones; they do no work and cannot sting. They are developed from unfertilized eggs, and their only job is to impregnate a queen. The queen must be fertilized in order to lay more worker eggs. During the season when less honey is available and the drone is of no further use, the workers block the drones from eating the honey so that they will starve to death.

According to the passage, honey is carried to the hive in a honey stomach by the.............

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks
Choosing clothes can be difficult. Some people want to be fashionable, but they don’t want to look exactly like everybody else. Not all clothes are (1)........ for work or school, perhaps because they are not formal enough, or simply not comfortable. It is easy to buy the (2).......... size, and find that your trousers are too tight, especially if you are a little bit overweight. Very (3)........clothes make you feel slim, but when they have shrunk in the washing machine, then you have the same problem! If you buy light cotton clothes, then they might not be (4)........ enough for winter. If your shoes are not waterproof and if you aren’t (5)....... for the cold, you might look good, but feel terrible!
(1).................................

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Puerto Rico, a Caribbean island rich in history and remarkable natural beauty, has a cuisine all its own. Immigration to the island has helped to shape its cuisine, with people from all over the world making various contributions to it. However, before the arrival of these immigrants, the island of Puerto Rico was already known as Borikén and was inhabited by the Taíno people. Taíno cuisine included such foods as rodents with sweet chili peppers, fresh shellfish, yams, and fish fried in corn oil.
Many aspects of Taíno cuisine continue today in Puerto Rican cooking, but it has been heavily influenced by the Spanish, who invaded Puerto Rico in 1508, and Africans, who were initially brought to Puerto Rico to work as slaves. (2)Taíno cooking styles were mixed with ideas brought by the Spanish and Africans to create new dishes. (3) Africans also added to the island’s food culture by introducing powerful, contrasting tastes in dishes like piñon–plantains layered in ground beef. In fact, much of the food Puerto Rico is now famous for—plantains, coffee, sugarcane, coconuts, and oranges—was actually imported by foreigners to the island. (4)
A common assumption many people make about Puerto Rican food is that it is very spicy. It’s true that chili peppers are popular; ajícaballero in particular is a very hot chili pepper that Puerto Ricans enjoy. However, milder tastes are popular too, such as sofrito. The 25 base of many Puerto Rican dishes, sofrito is a sauce made from chopped onions, garlic, green bell peppers, sweet chili peppers, oregano, cilantro, and a handful of other spices. It is fried in oil and then added to other dishes.

Which of the following is NOT true?

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A term 'megalopolis' (or megacity) was first used by French geographer Jean Gottman to describe the north-eastern United States in 1961. The term is used more widely now and is defined as an urban area of more than 10 million inhabitants dominated by a low-density housing. In 1995 there were 14 megacities. By 2020 there could be 30.
Megacities are the result of the process of urbanization. After cities grew into crowded urban centres, people who could afford to move into suburbs at the edge of the city. When the suburbs in turn became crowded, people moved into villages and dormitory towns outside the city, but within commuting distance. In this way, for the first time since industrialisation, the countryside began to gain population, whereas cities lost their inhabitants. In the 1980s St Louis and Detroit in the America lost between 35 and 47 per cent of their populations and London lost 15 per cent in the 20 years to 1971.
However, this movement away from cities does not mean that the city is dying. In fact it is spreading. From the old city develops a metropolitan area with many low-level urban developments. When these metropolitan areas merge together, they form megacities which contain over 10 million people. The largest of these is in America, called Boswash - a region over 300 miles long from Boston in the north to Washington, DC in the south with more than 44 million people. There are emerging megalopolises in Britain centred around London and the south-east, in Germany in the industrial region of the Ruhr and Japan in the Tokyo-Osaka-Kyoto region.

Which of the following is NOT true?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.
 In recent years there have been many articles on air pollution in newspapers and magazines. Scientists all over the world have warned that our atmosphere is (1).....more and more contaminated, and that Man, through his carelessness, may run out of pure air to breathe.
Automobiles and industries mainly account (2).... air pollution in most cities. They pour into the air such gases as carbon monoxide, sulfur and nitrogen oxides, (3)...... are very harmful to humans. (4)......still, these gases, a series of chemical changes, turn into toxic acids. They fall down in “acid rains”, raising the acidity in the air, soil and water to dangerous levels and affecting not only tress but also fish and other wildlife. Many industrial countries in Europe and North America have suffered bad effects (5)......those “rains”.
Surely, Man faces no more urgent problem than that of saving his own survival. Scientists, social organizations and governments shout sit down together to solve the air pollution problem.
(5).........................

Are organically grown foods the best food choices? The advantages claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others.
The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs.
Although most of these claims are not supported by scientific evidence, the preponderance of written material advancing such claims makes it difficult for the general public to separate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form the basis for folklore.
Almost daily the public is besieged by claims for “no-aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural vitamins are superior to synthetic ones, that fertilized eggs are nutritionally superior to unfertilized eggs, that untreated grains are better than fumigated grains, and the like.
One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases consumers are misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers, particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

The word “maintain” has closest meaning with ............

Choose the best answer:
When another old cave is discovered in the south of France, it is not usually news. Rather, it is an ordinary event. Such discoveries are so frequent these days that hardly anybody pays heed to them. However, when the Lascaux cave complex was discovered in 1940, the world was amazed. Painted directly on its walls were hundreds of scenes showing how people lived thousands of years ago. The scenes show people hunting animals, such as bison or wild cats. Other images depict birds and, most noticeably, horses, which appear in more than 300 wall images, by far outnumbering all other animals.
Early artists drawing these animals accomplished a monumental and difficult task. “They” did not limit themselves to the easily accessible walls but carried their painting materials to spaces that required climbing steep walls or crawling into narrow passages in the Lascaux complex.
Unfortunately, the paintings have been exposed to the destructive action of water and temperature changes, which easily wear the images away. Because the Lascaux caves have many entrances, air movement has also damaged the images inside. Although they are not out in the open air, where natural light would have destroyed them long ago, many of the images have deteriorated and are barely recognizable. To prevent further damage, the site was closed to tourists in 1963, 23 years after it was discovered.
3.Which title best summarizes the main idea of the passage?