Read the following passage and choose the best answer (A, B, C, D):
Aging is the process of growing old. It occurs eventually in every living thing provided, of course, that an illness or accident does not kill it prematurely. The most familiar outward signs of aging may be seen in old people, such as the graying of the hair and the wrinkling of the skin. Signs of aging in a pet dog or cat include loss of playfulness and energy, a decline in hearing and eyesight, or even a light graying of the coat. Plants are too, but the signs are much harder to detect. Most body parts grow bigger and stronger, and function more effiiently during childhood. They reach their peak at the time of maturity, or early adulthood. After that, they begin to decline. Bones, for example, gradually become lighter and more brittle. In the aged, the joints between the bones also become rigid and more inflxible. This can make moving very painful. All the major organs of the body show signs of aging. The brain, for example, works less effiiently, and even gets smaller in size. Thinking processes of all sorts are slowed down. Old people often have trouble in remembering recent events. One of the most serious changes of old age occurs in the arteries, the blood vessels that lead from the heart. They become thickened and constricted, allowing less blood to flw to the rest of body. This condition accounts, directly or indirectly, for many of the diseases of the aged. It may, for example, result in heart attack. Aging is not a uniform process. Different parts of the body wear out at the different rates. There are differences among people in their rate of aging. Even the cell of the body differ in the way they age. The majority of cells are capable of reproducing themselves many times during the course of a lifetime. Nerve cells and muscle fiers can never be replaced once they wear out. Gerontologists - scientists who study the process of aging - believe this wearing out of the body is controlled by a built-in biological time-clock. They are trying to discover how this clock works so that they can slow down the process. This could give man a longer life and a great number of productive years.
2. When does the human body begin to lose vigor and the ability to function effiiently?

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In the early twentieth century, an American woman named Emily Post wrote a book on etiquette. This book explained the proper behavior Americans should follow in many different social (1)______, from birthday parties to funerals. But in modern society, it is not simply to know the proper rules for behavior in your own country. It is necessary for people (2)______ work or travel abroad to understand the rules of etiquette in other cultures as well. Cultural (3)______ can be found in such simple processes as giving or receiving a gift. In Western cultures, a gift can be given to the receiver with relatively little ceremony. When a gift is offered, the receiver usually takes the gift and expresses his or her thanks. (4)______, in some Asian countries, the act of gift–giving may appear confusing to Westerners. In Chinese culture, both the giver and receiver understand that the receiver will typically refuse to take the gift several times before he or she finally accepts it. In addition, to (5)______ respect for the receiver, it is common in several Asian cultures to use both hands when offering a gift to another person.

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Once restricted to space stations and satellites, photovoltaics are now gaining popularity and becoming an increasingly viable option. Every day, the sun releases an enormous amount of energy, far more than the entire population consumes. Being that the sun is a sustainable, renewable, and inexhaustible source for generating electricity, not using it seems almost counter-intuitive, especially considering the social and environmental impacts of other forms of energy generation. But the technology to create electricity from the sun is by no means simple and still has some limitations, the most significant being price. The process of turning the sun’s rays into electrical energy all starts in the so-called photovoltaic cell. These cells are produced with two chemically altered silicon layers of which one is missing elections and the other is electron-overloaded. When the photons from the sunlight reach the surface, these electrons gain the ability to move, generating a flow that creates an electric current. Each cell generates a small amount of energy and a panel is usually made of between 36 and 72 photovoltaic cells. By connecting several panels together, a photovoltaic system is created. Eight to ten panels is enough to power a small house. Evidently, however, this statistic is influenced by some factors, such as the efficiency of the panels, the amount of sunshine in the region, and the energy demand of the residence itself.  Importantly, photovoltaic solar panels produce electricity in the form of direct current, meaning the electricity must pass through an inverter to transform it into alternating current - which is what is normally used in buildings, appliances, sockets, and light bulbs. Photovoltaic systems can facilitate energy generation in remote locations where infrastructural networks do not reach. In these cases, the system uses batteries to store electricity when less energy is used than is consumed, such as at night or on very cloudy days. However, it is also possible to use photovoltaics in systems connected to the power grid. In these cases, the excess energy goes to the electricity grid, creating energy “credits” for the building in question. In some countries, it is even possible to sell surplus energy, making the building a power plant for neighbors and method of paying off the investment more quickly.  
1. Which best serves as the title for the passage?

Read the following passage and choose the best answer (A, B, C, D):
Once restricted to space stations and satellites, photovoltaics are now gaining popularity and becoming an increasingly viable option. Every day, the sun releases an enormous amount of energy, far more than the entire population consumes. Being that the sun is a sustainable, renewable, and inexhaustible source for generating electricity, not using it seems almost counter-intuitive, especially considering the social and environmental impacts of other forms of energy generation. But the technology to create electricity from the sun is by no means simple and still has some limitations, the most significant being price. The process of turning the sun’s rays into electrical energy all starts in the so-called photovoltaic cell. These cells are produced with two chemically altered silicon layers of which one is missing elections and the other is electron-overloaded. When the photons from the sunlight reach the surface, these electrons gain the ability to move, generating a flow that creates an electric current. Each cell generates a small amount of energy and a panel is usually made of between 36 and 72 photovoltaic cells. By connecting several panels together, a photovoltaic system is created. Eight to ten panels is enough to power a small house. Evidently, however, this statistic is influenced by some factors, such as the efficiency of the panels, the amount of sunshine in the region, and the energy demand of the residence itself.  Importantly, photovoltaic solar panels produce electricity in the form of direct current, meaning the electricity must pass through an inverter to transform it into alternating current - which is what is normally used in buildings, appliances, sockets, and light bulbs. Photovoltaic systems can facilitate energy generation in remote locations where infrastructural networks do not reach. In these cases, the system uses batteries to store electricity when less energy is used than is consumed, such as at night or on very cloudy days. However, it is also possible to use photovoltaics in systems connected to the power grid. In these cases, the excess energy goes to the electricity grid, creating energy “credits” for the building in question. In some countries, it is even possible to sell surplus energy, making the building a power plant for neighbors and method of paying off the investment more quickly.  
4. The word “surplus” in paragraph 4 is closest in meaning to _______

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

When oil or coal is burnt, a great number of smoke that contains some kinds of acid is produced

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 emitted in industrial areas represents a threat to human health and the surrounding natural resources. We have a tendency to believe that the production processes are the only source of environmental damage, and often forget about the possible long-term effects of harmful production practices. We may think that the closure of these huge industrial areas would improve the quality of the environment. Unfortunately, this ignores the threat of the remaining waste, which is abandoned and poorly stored. It represents an even bigger danger because it stands neglected as it degrades and leaks into the earth without any control at all.
Changes in the water chemistry due to surface water contamination can affect all levels of an ecosystem. It can affect the health of lower food chain organisms and, consequently, the availability of food up through the food chain. It can damage the health of wetlands and damage their ability to support healthy ecosystems, control flooding, and filter pollutants from storm water runoff. The health of animals and humans are affected when they drink or bathe in contaminated water. In addition water-based organisms, like fish and shellfish, can pile up and concentrate contaminants in their bodies. When other animals or humans eat these organisms, they receive a much higher dose of contaminant than they would have if they had been directly exposed to the original contamination.
Contaminated groundwater can badly affect animals, plants and humans if it is removed from the ground by manmade or natural processes. Depending on the study of rocks of the area, groundwater may rise to the surface through springs or seeps, flow sideways into nearby rivers, streams, or ponds, or sink deeper into the earth. In many parts of fhe world, groundwater is pumped out of the ground to be used for drinking, bathing, other household uses, agriculture, and industry.
Contaminants in the soil can harm plants when they take up the contamination through their roots. Eating, breathing in, or touching contaminated soil, as well as eating plants or animals that have piled up soil contaminants can badly affect the health of humans and animals.
Air pollution can cause breathing-related  problems  and  other  bad  health  effects  as  contaminants  are absorbed from the lungs into other parts of the body. Certain air contaminants can also harm animals and humans when they contact the skin. Plants rely on breathing for their growth and can also be affected by exposure to contaminants moved in the air.

Which of the followings has the closest meaning to the word “absorbed” in the last paragraph?

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

His parents don’t allow him staying out late on weekdays.

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A Tidal Stream Generation system reduces some of the environmental effects of tidal barrages by using turbine generators beneath the surface of the water. Major tidal flows and ocean currents, like the Gulf Stream, can be exploited to extract its tidal energy using underwater rotors and turbines. Tidal stream generation is very similar in principle to wind power generation. Water currents flow across a turbines rotor blades which rotates the turbine, much like how wind currents turn the blades for wind power turbines. In fact, tidal stream generation areas on the sea bed can look just like underwater wind farms. Unlike off-shore wind power which can suffer from storms or heavy sea damage, tidal stream turbines operate just below the sea surface or are fixed to the sea bed. Tidal streams are formed by the horizontal fast flowing volumes of water caused by the ebb and flow of the tide as the profile of the sea bed causes the water to speed up as it approaches the shoreline. As water is much more denser than air and has a much slower flow rate, tidal stream turbines have much smaller diameters and higher tip speed rates compared to an equivalent wind turbine. Tidal stream turbines generate tidal power on both the ebb and flow of the tide. One of the disadvantages of Tidal Stream Generation is that as the turbines are submerged under the surface of the water they can create hazards to navigation and shipping. Other forms of tidal energy include tidal fences which use individual vertical-axis turbines that are mounted within a fence structure, known as the caisson, which completely blocks a channel and force water through them. Another alternative way of harnessing tidal power is by using an “oscillating tidal turbine”. This is basically a fixed wing called a Hydroplane positioned on the sea bed. The hydroplane uses the energy of the tidal stream flowing past it to oscillate its giant wing, similar to a whales flipper, up and down with the movement of the tidal currents. This motion is then used to generate electricity. The angle of the hydroplane to the flow of the tide can be varied to increase efficiency. Tidal energy is another form of low-head hydro power that is completely carbon neutral like wind and hydro energy. Tidal power has many advantages compared to other forms of renewable energy with its main advantage being that it is predictable. However, like many other forms of renewable energy, tidal energy also has its disadvantages such as its inflexible generation times dependant upon the tides and the fact that it operates in the hostile conditions of the oceans and seas
6. What can be inferred from paragraph 5?

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:
Four West Indian geckos, with human assistance, have recently entered the United States. The yellowheaded gecko, the ashy gecko, the reef gecko, and the ocellated gecko are presently inhabiting the tropical areas of the Keys and the tip of southern Florida. The Mediterranean gecko also arrived along the Gulf coast some time ago, via the West Indies. The only other geckos in the United States live in the Southwest. In extreme southern California, the leaf-gingered gecko lives

in dry, rocky country and scampers over boulders at night, hiding by day in crevices. It has a slender, tapered tail and stalks insects by raising itself high on its legs, cocking its head, and twitching its tail nervously before leaping on its prey. In courtship, the tail is also waved by the male as he approaches the female.
Although most lizards are excellent climbers, the geckos are able to walk on smooth surfaces with the help of unique clinging devices under the toes. Also, the undersides of most geckos have pads of large scales, each of which bear microscopic hairs with hundreds of branches having minute, blunt ends that press against the surface that the gecko is on, enabling the gecko to cling to almost any surface. Like other lizards, geckos have the ability to shed their tails if attacked by an enemy. They stump heels and a new tail is grown in approximately the same shape as the original. Unlike most lizards, most geckos have no moveable eyelids. The nocturnal geckos have vertical pupils, which contract in bright light. All geckos, except several New Zealand species, lay eggs. The eggs have a tough, white shell and are laid under stones, behind window shutters or under bark.

The passage would be most interest to...

Swine influenza (also called swine flu, hog flu and pig flu) is an infection of a host animal by any one of several specific types of microscopic organisms called "swine influenza virus". A swine influenza virus (SIV) is any strain of the influenza family of viruses that is usually hosted by (is endemic in) pigs. As of 2009, the known SIV strains are the influenza c virus and the subtypes of the influenza A virus known as HI N1, H1N2, H3N1, H3N2 and H2N3. Swine influenza is common in pigs in the mid-western United States (and occasionally in other states), Mexico, Canada, South America, Europe (including the UK, Sweden and Italy) Kenya Mainland China, Taiwan Japan and other parts of eastern Asia.

Transmission of swine influenza vims from pigs to humans is not common and does not always cause human influenza, often only resulting in the production of antibodies in the blood. The meat of the animal poses no risk of transmitting the virus when properly cooked. If transmission does cause human influenza, it is called zoonotic swine flu. People who work with pigs, especially people with intense exposures, are at increased risk of catching swine flu. In the mid-20th century, identification of influenza subtypes became possible. This allows accurate diagnosis of transmission to humans. Since then, fifty confirmed transmissions have been recorded. Rarely, these strains of swine flu can pass from human to human. In humans, the symptoms of swine flu are similar to those of influenza and of influenza-like illness in general namely chills fever sore throat, muscle pains severe headache, coughing, weakness and general discomfort.

The 2009 flu outbreak in humans known as "swine flu" is due to a new strain of influenza A virus subtype H1N1 that contains genes closely related to swine influenza. The origin of this new strain is unknown. However, the World Organization for Animal Health (OIE) reports that this strain has not been isolated in pigs. This strain can be transmitted from human to human, and causes the normal symptoms of influenza.

The word "intense" is closest in meaning to .......

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The human desire for companionship may feel boundless, but research suggests that  our social capital is finite. Social scientists have used a number of ingenious approaches to gauge the size of people’s social networks; these have returned estimates ranging from about 250 to about 5,500 people. An undergraduate thesis from MIT focusing exclusively on Franklin D. Roosevelt, a friendly guy with an especially social job, suggested that he might have had as many as 22,500 acquaintances. Looking more specifically at friendship, a study using the exchange of Christmas cards as a proxy for closeness put the average person’s friend group at about 121 people.  However vast our networks may be, our inner circle tends to be much smaller. The average American trusts only 10 to 20 people. Moreover, that number may be shrinking: From 1985 to 2004, the average number of confidants that people reported having decreased from three to two. This is both sad and consequential, because whoever has strong social relationships tends to live longer than those who don’t. So what should you do if your social life is lacking? Just follow the research. To begin with, don’t dismiss the humble acquaintance. Even interacting with people with whom one has weak social ties has a meaningful influence on well-being. Beyond that, building deeper friendships may be largely a matter of putting in time. A recent study out of the University of Kansas found that it takes about 50 hours of socializing to go from acquaintance to casual friend, an additional 40 hours to become a “real” friend, and a total of 200 hours to become a close friend. If that sounds like too much effort, reviving dormant social ties can be especially rewarding. Reconnected friends can quickly recapture much of the trust they previously built, while offering each other a dash of novelty drawn from whatever they’ve been up to in the meantime. And if all else fails, you could start randomly confiding in people you don’t know that well in hopes of letting the tail wag the relational dog. The academic literature is clear: Longing for closeness and connection is pervasive. Which suggests that most of us are stumbling through the world pining for companionship that could be easily provided by the lonesome stumblers all around us.
3. The word “those” in paragraph 2 refers to _____

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Bacteria are the smallest known living things with a cellular structure. These colorless, one-celled micro-organisms exist (1) ______ organic matter is found: in soil, in water and in the air. Since most of them have no chlorophyll, they cannot use light energy to synthesize their food, (2) ________ green plants do. They must get their food in other ways. In this, bacteria resemble animals. However, since/as they are enclosed in a cell wall, they can only (3) _______ dissolved food like plants do. Although most bacteria do not contain chlorophyll, some of them can make their own organic food from simple inorganic (4)________. They do not, however, use light energy for this purpose. Others get ready-made food from dead plants and animals. Still others are parasites. Parasites are (5)______ to enter other living organisms and take food from them. In doing so, they often cause diseases or the death of their hosts

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A ____________ is a short funny film with drawn characters.

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………… you work harder, you will be sacked.

Find mistake:
It’s said that huge progress has made in lots of fields of science in the last few years.

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

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The past fifty years or so have seen the gradual disappearing of animals from this earth, fishes from the sea, trees and plants from the land. Many factors result in this unpleasant phenomenon. Among them, hunting is the main factor that endangers wildlife. Some people kill wildlife for sport. They take pleasure in collecting heads and hides. Yet others specialize in commercial hunting like killing whales. Apart from this, the rapidly growing human population threatens wildlife on land, too. Towns expand and roads have to be built, so forests are burnt and trees are chopped down. It seems that man needs every inch of land within his reach, so he moves on to the natural habitat of wildlife. Tigers, lions and leopards slowly die off without the food and shelter that the forests provide. In addition, rapid urbanization means industrial expansion. Very often, poisonous chemicals, industrial wastes and oil are dumped into the rivers and seas. Fish and birds are threatened. Man depends greatly on animals for survival. He needs their flesh, hides and furs. Thus, man cannot do without wildlife; or he himself would become extinct. The public should be made aware that it would be better to shoot the animals with a camera than with a gun. In this way, they can preserve and help wildlife to continue living rather than to remove all signs of it. Man must learn to farm the sea as he does the land. He should regulate the amount and the frequency of his catch. He should allow fish to breed and multiply before netting them. Man also needs to build forest reserves, and to pass laws prohibiting the killing of animals, especially those that are already rare. To retain the present animal kingdom, the least that man can do is to clean the seas and rivers and to prevent pollution. The cycle of nature is such that it forms a vicious circle. The insecticides and pesticides that we spray on crops can kill the birds and animals that feed on them. When man eats these poisoned animals, he himself can die. We must therefore test the chemicals to be used before they are sprayed or it might mean the death of man!
1. The author’s purpose in writing the passage is to __________

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Green-space facilities are contributing to an important extent to the quality of the urban environment. Fortunately it is no longer necessary that every lecture or every book about this subject has to start with the proof of this idea. At present, it is generally accepted, although more as a self-evident statement than on the base of a closely-reasoned scientific proof. The recognition of the importance of green-spaces in the urban environment is a first step on the right way; this does not mean, however, that sufficient details are known about the functions of green-space in towns and about the way in which the inhabitants are using these spaces. As to this rather complex subject I shall, within the scope of this lecture, enter into one aspect only, namely the recreative function of green-space facilities. The theoretical separation of living, working, traffic and recreation which for many years has been used in town-and-country planning, has in my opinion resulted in disproportionate attention for forms of recreation far from home, whereas there was relatively little attention for improvement of recreative possibilities in the direct neighbourhood of the home. We have come to the conclusion that this is not right, because an important part of the time which we do not pass in sleeping or working, is used for activities as possible, and the design of these has to be such that more obligatory activities can also have a recreative aspect. The very best standard of living is nothing if it is not possible to take a pleasant walk in the district, if the children cannot be allowed to play in the streets, because the risks of traffic are too great, if during shopping you can nowhere find a spot for enjoying for a moment the nice weather, in short, if you only feel yourself at home after the street-door of you house is closed after you.  
5. The author suggests that the recreative possibilities of green-space should be provided ____

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All plants rely on nutrients taken from the soil in order to survive. However, in areas where the soil does not contain enough (35)_____ nutrients, some plants have adapted to (36) _____ their diets from another source: living organisms. Though they are few in number, carnivorous plants are (37)_____ fascinating beings that ―eat‖ anything from one-celled organisms to insects in order to survive. They are commonly found in marshlands. Carnivorous plants feature one of several types of ―traps‖ to ensnare prey, which they consume to make up for nutrients that may be missing from the soil. While there are over 400 species of carnivorous plants in the world today, some are more (38)_____ than others. The most well-known of these plants are the snap traps, which include the Venus flytrap. Snap traps are easily identified by their leaves, which are separated into two lobes that have the ability to fold together. Inside the lobes, the surface is covered with tiny hairs that are (39) _____ to movement. When the plant‘s prey brushes against the hairs, it triggers a closing mechanism that rapidly brings the two lobes together, trapping the prey (40)_____ inside. The response of the traps is phenomenal (41)_____ speed: the time between triggering the hairs and snapping shut is less than a second. As the prey struggles inside the trap, it only triggers more hairs, causing the leaves to tighten their (42) _____. The plant then secrets liquid chemicals from special glands into the trap to dissolve the prey and absorb all of its nutrients. Besides the Venus flytrap, only one other type of snap trap exists today, (43)_____ to as the waterwheel plant. The two share a common ancestor and differ only in a few ways. For instance, the waterwheel is an aquatic plant, while the flytrap is exclusively terrestrial. In addition, the flytrap feeds primarily on arthropods like spiders, while the waterwheel lives (44)_____ simple invertebrates, like certain types of plankton

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The aviation industry, especially the commercial aviation sector, is constantly striving to improve both the way it works and its customer satisfaction. It has begun using artificial intelligence. Though AI in the aviation industry is still in the nascent stage, some progress has been made already as certain leading carriers invest in AI. To make a long story short, AI can redefine how the aviation industry goes about its work. In 2017, American Airlines conducted an app development competition with the goal of having an app developed for making baggage screening easier for passengers. The competition, named HackWars, was themed upon artificial intelligence, drones and augmented and virtual reality. The winner, known as “Team Avatar,” developed an app that would not only allow passengers determine their baggage size before arriving at the airport, but also prepay any potential baggage-related expenses. United Airlines is using Amazon’s Alexa to have certain common customer queries answered. In September 2017, United announced a collaboration with Alexa. The feature is known as the United skill. To get started, all passengers need to do is to  add the United skill to their Alexa app and then start asking questions. Alexa answers common queries correctly, such as the status of a flight by number, check-in requests and availability of Wi-Fi on a flight. The reviews so far have been mixed, which points to the fact that there is a learning curve, and it is still a long way to go before AI can fully handle customer assistance. Tracking progress is an enormous challenge that airlines will face. The first thing they need to do is to develop analytics that will help them develop and process accurate data. However, that in itself is a challenge. What kind of analytics will help? For example, customer satisfaction is going to be one of the most important factors in success. What kind of analytics will determine that airlines have been improving on customer satisfaction parameters? AI needs huge investments, and probably the biggest risk in this is smaller, especially budget airlines are going to miss out on reaping the benefits of AI fully. Does that mean that the performance of the smaller carriers will be impacted? That might not be the case, because we might be moving toward more acquisitions and mergers. Bigger airlines will have a massive appetite for acquiring smaller airlines with an eye on the market. It is not all gloom and doom though, because smaller airlines like Southwest have already shown some initiatives toward embracing AI. It is surprising that a sector as important as aviation has woken up to AI so late. As AI in aviation picks up its pace, there could probably be a few mergers, acquisitions or even closure of small airlines which will not be able to afford the investments. Now, AI seems the best option to take aviation to the next level.
3. What does author want to convey in paragraph 2?

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:
Over the past 600 years, English has grown from a language of few speakers to become the dominant language of international communication. English as we know it today emerged around 1350, after having incorporated many elements of French that were introduced following the Norman invasion of 1066. Until the 1600s, English was, for the most part, spoken only in England and had not extended even as far as Wales, Scotland or Ireland. However, during the course of the next two centuries, English began to spread around the globe as a result of exploration, trade (including slave trade), colonization, and missionary work. Thus, small enclaves of English speakers became established and grew in various parts of the world. As these communities proliferated, English gradually became the primary language of international business, banking and diplomacy.
Currently, about 80 percent of the information stored on computer systems worldwide is in English. Two-thirds of the world’s science writing is in English, and English is the main language of technology, advertising, media, international airports, and air traffic controllers. Today there are more than 700 million English users in the world, and over half of these are non-native speakers, constituting the largest number of non-native users than any other language in the world.

Approximately when did English begin to be used beyond England?