Choose the best answer:
Co Loa was the capital of Early Ngo Dynasty, ___________ in fact it only existed with the proper function of a capital in 6 years under Ngo Quyen’s reign.

 

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Climate change, also called global warming, refers to the rise in average surface temperatures on Earth. An overwhelming scientific consensus maintains that climate change is due primarily to the human use of fossil fuels, which (1) __________ carbon dioxide and other greenhouse gases into the air. The gases trap heat within the atmosphere, which can have a range of effects on ecosystems, (2) __________ rising sea levels, severe weather events, and droughts that render landscapes more susceptible to wildfires. While consensus among nearly all scientists, scientific organizations, and governments is (3)__________ climate change is happening and is caused by human activity, a small minority of voices questions the validity of such assertions and prefers to cast doubt on the preponderance of evidence. Climate change deniers often claim that recent changes (4) __________ to human activity can be seen as part of the natural variations in Earth’s climate and temperature, and that it is difficult or impossible to establish a direct connection between climate change and any single weather event, such as a hurricane. While the latter is generally true, decades of data and analysis support the reality of climate change and the human factor in this process. In any case, economists agree that acting to reduce fossil fuel emissions would be far less expensive than (5) __________ with the consequences of not doing so

Read the following passage and choose the best answer (A, B, C, D):
Practical experience is a must-have for today’s job seekers. According to Brazen Life’s Huffington Post article titled “Why Gaining Work Experience Is More Important Than Your Education,” many colleges and universities report that students who have completed an internship or gained work experience during their studies have higher rates of getting hired. For example, at Iowa State University, of all students who completed a co-op program to earn a BS in engineering, an astounding 90 percent got jobs after graduation. Why is practical experience so important? There are a number of reasons why you need practical work experience. First, it’s simply the smart thing to do when you’re preparing for a career in a specific field. Let’s say it’s your dream to work as a consultant for an international corporate relocation company because you love international travel and you like organizing things. So you get a part-time job working as an office assistant at a corporate relocation company… and you find out it’s very different from what you expected. In short, you realize this isn’t the job for you-and you can concentrate on finding another job where you can put your passion and skills to work, for example in the tourism industry. Alternatively, you might find out that you enjoy the corporate relocation business. That means you’re gaining invaluable industry experience that will look great on your resumé when you apply for a full-time job.  Second, practical work experience teaches valuable soft skills, such as discipline, perseverance, teamwork, leadership skills, communication skills and problem solving. Employers will look for these in candidates and they’ll want to see proof. If you’ve spent a month as a team leader at Homes for Heroes, the leadership skills, teamwork experience and problem-solving abilities you developed there can add significant value to your candidacy. Third, working helps you build your network and can provide you with contacts in your chosen field. These contacts can be extremely useful when it comes to hearing about job leads and interesting opportunities. In addition, if you’ve impressed someone, he or she might be willing to write you a letter of recommendation for a job or a place in a graduate program.  Finally, the company you’re working for might offer you a position after you’ve graduated. Your employer already knows your skills and abilities, and you’re already acquainted with the company-so it’s a win-win situation! 
7. The word “acquainted” in paragraph 4 is closest in meaning to _______

Read the following passage and choose the best answer (A, B, C, D):
When Gustave Eiffel’s company built Paris’ most recognizable monument for the 1889 World’s Fair, many regarded the massive iron structure with skepticism. Today, the Eiffel Tower, which continues to serve an important role in television and radio broadcasts, is considered an architectural wonder and attracts more visitors than any other paid tourist attraction in the world. In 1889, Paris hosted an Exposition Universelle (World’s Fair) to mark the 100-year anniversary of the French Revolution. More than 100 artists submitted competing plans for a monument to be built on the Champ-de-Mars, located in central Paris, and serve as the exposition’s entrance. The commission was granted to Eiffel et Compagnie, a consulting and construction firm owned by the acclaimed bridge builder, architect and metals expert Alexandre-Gustave Eiffel. While Eiffel himself often receives full credit for the monument that bears his name, it was one of his employees - a structural engineer named Maurice Koechlin—who came up with and fine-tuned the concept. Several years earlier, the pair had collaborated on the Statue of Liberty’s metal armature. Eiffel reportedly rejected Koechlin’s original plan for the tower, instructing him to add more ornate flourishes. The final design called for more than 18,000 pieces of puddle iron, a type of wrought iron used in construction, and 2.5 million rivets. Several hundred workers spent two years assembling the framework of the iconic lattice tower, which at its inauguration in March 1889 stood nearly 1,000 feet high, and was the tallest structure in the world - a distinction it held until the completion of New York City’s Chrysler Building in 1930. In 1957, an antenna was added that increased the structure’s height by 65 feet, making it taller than the Chrysler Building but not the Empire State Building, which had surpassed its neighbor in 1931. Initially, only the Eiffel Tower’s second-floor platform was open to the public; later, all three levels, two of which now feature restaurants, would be reachable by stairway or one of eight elevators. Millions of visitors during and after the World’s Fair marveled at Paris’ newly erected architectural wonder. Not all of the city’s inhabitants were as enthusiastic, however: Many Parisians either feared it was structurally unsound or considered it an eyesore. The novelist Guy de Maupassant, for example, allegedly hated the tower so much that he often ate lunch in the restaurant at its base, the only vantage point from which he could completely avoid glimpsing its looming silhouette.  
3. The word “granted” in paragraph 1 is closest in meaning to ______

Find synonym:
The government's interference in the strike has been widely criticised

Read the following passage and choose the best answer (A, B, C, D):
Geothermal energy is the heat from the Earth. It’s clean and sustainable. Resources of geothermal energy range from the shallow ground to hot water and hot rock found a few miles beneath the Earth’s surface, and down even deeper to the extremely high temperatures of molten rock called mác-ma. Almost everywhere, the shallow ground or upper 10 feet of the Earth’s surface maintains a nearly constant temperature between 50° and 60°F (10° and 16°C). Geothermal heat pumps can tap into this resource to heat and cool buildings. A geothermal heat pump system consists of a heat pump, an air delivery system (ductwork), and a heat exchanger-a system of pipes buried in the shallow ground near the building. In the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to provide a free source of hot water. In the United States, most geothermal reservoirs of hot water are located in the western states, Alaska, and Hawaii. Wells can be drilled into underground reservoirs for the generation of electricity. Some geothermal power plants use the steam from a reservoir to power a turbine/generator, while others use the hot water to boil a working fluid that vaporizes and then turns a turbine. Hot water near the surface of Earth can be used directly for heat. Direct-use applications include heating buildings, growing plants in greenhouses, drying crops, heating water at fish farms, and several industrial processes such as pasteurizing milk. Hot dry rock resources occur at depths of 3 to 5 miles everywhere beneath the Earth’s surface and at lesser depths in certain areas. Access to these resources involves injecting cold water down one well, circulating it through hot fractured rock, and drawing off the heated water from another well. Currently, there are no commercial applications of this technology. Existing technology also does not yet allow recovery of heat directly from mác-ma, the very deep and most powerful resource of geothermal energy 
6. What is the main information of the last paragraph?

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There is a new type of advertisement becoming increasingly common in newspaper classified columns. It is sometimes placed among “situations vacant”, although it does not offer anyone a job, and sometimes it appears “situations wanted”, although it is not placed by someone looking for a job, either. What it does is to offer help in applying for a job. “Contact us before writing your application”, or "Make use of our long experience in preparing your curriculum vitae or job history”, is how it is usually expressed. The growth and apparent success of such a specialized service is, of course, a reflection on the current high levels of unemployment. It is also an indication of the growing importance of the curriculum vitae (or job history), with the suggestion that it may now qualify as an art form in its own right. There was a time when job seekers simply wrote letters of application. “Just put down your name, address, age and whether you have passed any exams”, was about the average level of advice offered to young people applying for their first jobs when I left school. The letter was really just for openers, it was explained, everything else could and should be saved for the interview. And in those days of full employment, the technique worked. The letter proved that you could write and were available for work. Your eager face and intelligent replies did the rest. Later, as you moved up the ladder, something slightly more sophisticated was called for. The advice then was to put something in the letter which would distinguish you from the rest. It might be the aggressive approach. “Your search is over. I am the person you are looking for,” was a widely used trick that occasionally succeeded. Or it might be some special feature specially designed for the job in view  
7. What does the word "which” in the fourth paragraph refer to?

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

John’s wisdom teeth were troubling him, so he went to a dental surgeon to see about having them pull

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the best option for each of the blanks.
 The Rocky Mountains run almost the length of North America. They start in the North West, but lie only a (1)...........hundred miles from the centre in the more southern areas. Although the Rockies are smaller (2)............. the Alps, they are no less beautiful.
There are many roads across the Rockies, but the best way to see them is to travel by train. You start from Vancouver, the most attractive of Canada’s big cities. Standing with its feet in the water and its (3).........in the mountains, this city (4)................its residents to ski on slopes just 15 minutes by car from the city centre.
Thirty passenger trains a day used to (5)................off from Vancouver on the cross–continent railway. Now there are just three a week, but the ride is still a great adventure. You sleep on board, which is fun, but travel through some of the best site at night.

(1)...............................

Read the following passage and choose the best answer (A, B, C, D):
An individual’s personality is the complex of mental characteristics that makes them unique from other people. It includes all of the patterns of thought and emotions that cause us to do and say things in particular ways. At a basic level, personality is expressed through our temperament or emotional tone. However, personality also colors our values, beliefs, and expectations. There are many potential factors that are involved in shaping a personality. These factors are usually seen as coming from heredity and the environment. Research by psychologists over the last several decades has increasingly pointed to hereditary factors being more important, especially for basic personality traits such as emotional tone. However, the acquisition of values, beliefs, and expectations seem to be due more to socialization and unique experiences, especially during childhood. Some hereditary factors that contribute to personality development do so as a result of interactions with the particular social environment in which people live. For instance, your genetically inherited physical and mental capabilities have an impact on how others see you and, subsequently, how you see yourself. Likewise, your health and physical appearance are likely to be very important in your personality development. You may be frail or robust. You may have a learning disability. You may be slender in a culture that considers obesity attractive or vice versa. These largely hereditary factors are likely to cause you to feel that you are nice-looking, ugly, or just adequate. Likewise, skin color, gender, and sexual orientation are likely to have a major impact on how you perceive yourself. Whether you are accepted by others as being normal or abnormal can lead you to think and act in a socially acceptable or marginal and even deviant way. There are many potential environmental influences that help to shape personality. Child rearing practices are especially critical. In the dominant culture of North America, children are usually raised in ways that encourage them to become self-reliant and independent. Children are often allowed to act somewhat like equals to their parents. Children are given allowances and small jobs around the house to teach them how to be responsible for themselves. In contrast, children in China are usually encouraged to think and act as a member of their family and to suppress their own wishes when they are in conflict with the needs of the family. Independence and self-reliance are viewed as an indication of family failure and are discouraged.
1. According to recent studies, what factor is the most important in shaping an individual’s basic personality traits?

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It’s probably the most painstaking, heart wrenching, and stress inducing test of dedication a marriage can face. But the reward at the end is pretty sweet. At the annual Wife Carrying World Championships in Sonkajärvi, Finland, male competitors race around a track hauling their female partners on their backs. Winner takes home his wife’s weight in beer. It’s no ordinary racetrack, either. Competitors must wade through a neck-deep pool of water, climb over hurdles, and run through pits of sand before crossing the finish line. While some participants don crazy costumes for the pre-race, the actual event is pretty straightlaced. Wives must weigh at least 49 kilograms (108 pounds). Any woman lighter than that is required to carry a heavy rucksack until she reaches this minimum. A participant who drops his wife will be penalized 15 seconds. But there is one catch: contestants don’t have to carry their own wives. A friend’s wife, stranger’s wife, or even a random grandmother will do – as long as she’s over 17. Contestants flock from 47 countries across the globe to show their stuff in this epic display of brute strength. This year, Finnish couple Taisto Miettinen and Kristiina Haapanen captured the title for the fourth consecutive year. The 46-year-old lawyer and his wife completed the 235-meter course in one minute and four seconds. Like any dedicated athlete, Miettinen reported that he’d been training for a while. “In last autumn, I started running in the track, one hundred, two hundred and four hundred meters,” Miettinen said in a post-race interview. He also practiced the course in ski boots to build leg strength. The competition, which began in 1992, is supposedly rooted in the legend of Ronkainen the Robber — a hardnosed gang leader who hazed potential members by making them lug sacks of grain or live pigs over a similar course. He and his comrades also made a habit of stealing women from neighboring villages as a nod to this practice, many men “steal” friends’ wives for the competition. If you want to compete but can’t make it to Finland, there’s a North American version of the contest held in October at Sunday River Resort in Maine. With 100-plus pounds of brewski on the line, you might want to tell your significant other to start shaping up.
4. According to paragraph 2, Which of the following is NOT mentioned as a task for competitors to cross on the racetrack?

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As communities across the U.S. replace forests and woodlands with housing developments and other new construction, researchers are noting an increase in Lyme disease. To help prevent the spread of Lyme disease, Dr. Ivan Castro-Arellano, a disease ecologist and wildlife researcher at Texas State University, is exploring how urbanization and its effects on mammals impact the spread of pathogens.  Lyme disease, which spreads from animals to humans, is one of the fastest growing zoonotic diseases in the United States. Counties considered high-risk for Lyme disease grew 300% between 1993 and 2012. Caught quickly, Lyme disease is easily treated with antibiotics, but if it goes untreated it can lead to chronic issues such as Lyme arthritis, facial palsy and impaired memory. Many such zoonotic diseases have been increasing globally, researchers say, partially because of the displacement of animals. While medium- and large-sized mammals are displaced or eradicated by the removal of forested areas, whitefooted mice and deer thrive in small patches of green space. Mice and deer are contributing to favorable conditions for an increase in the ticks that spread the pathogens causing Lyme disease. Although East Texas has a similar pattern of woodland space compared to new construction as the northeast United States, Texas contract the disease at lower rates. This fact piqued the interest of Castro-Arellano. In addition to studying the area where the disease is prevalent, he decided to study where the disease is not prevalent to find keys to prevention. Castro-Arellano is part of a team of biologists, veterinarians and biomedical researchers that have been collecting samples and trying to understand what makes East Texas different. He believes that the climate, or certain species of East Texas mammals who kill ticks, could be contributing to the reduced tick population in East Texas.
5. According to paragraph 4, why did Castro-Arellano choose to study East Texas area?

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Being part of a community with long history rooted in agriculture, Vietnamese people  especially those from older generations hold a strong belief for superstition about luck and bad luck. Even though people have become much less superstitious as they were before, some traditions still (1) ____ on until today like people’s habit. Let’s take a closer look at some common food-related superstitions and explore the reasoning behind them.  Regarding what food to avoid before taking an important examination, homophones and the shape of your food comes into (2) ____. These features are the criteria that people use to decide which food is good and what is bad to eat before an important examination. Students are restrained from eating bananas prior to an exam for (3) ____ of failing ‘like sliding on a banana skin’  They are also advised eating squid, which when disturbed, emit a substance that is ‘as black as ink’. The phrase carries the connotation of a black (bad) mark on your test. Eating squash, pumpkin, melon and peanuts was also a (4) ____. The words for pumpkin and melon in Vietnamese mean “stuck” and the word for peanut means to be ‘lost’ or ‘digress’. Duck meat and eggs are associated with bad luck since the shape of an egg resembles the zero number. On the (5) ____, eating any type of beans is considered good before an exam since bean in Vietnamese means the same thing with to ‘pass a test’

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We’re not surprised if you haven’t been following the recent developments in AI all  that closely because, for the most part, it’s seemed like nothing exciting has happened for quite a long time. Sci-fi dreams about computer powered best friends aside, AI for the general public has come to mean reasonably responsive and well-programmed computer assistance rather than independent thinking machines. Concepts like ‘smart’ chatbots somehow seem to pull us further from the Star Trek or Heinlinian dream of fully sentient and intuitive computers while many products and services that claim to integrate AI seem to be nothing more than a fast way to analyze large amounts of data.  In fact, the last time most of us heard something hopeful about AI was when Deep Blue beat the world Chess champion, but what ever came of that AI? Surely it hasn’t used that incredible logical power to take over the world or begin making friends, so what do we even care?  While practical applications for specifically built AI are growing, the tradition of training your AI programming skills on classic strategy games has existed since the 1950s when a computer was programmed to play and was able to win a game of tic-tac-toe. Since then a large variety of games and custom-built AIs have been tested against each other to the great entertainment of experts in the field and curious nerds like us who care about that sort of thing. The real difference is not what they’re programmed for but how they are programmed to start with and, in fact, this is also what most profoundly distinguishes AlphaGo from its older-generation relative, the Chess champion DeepBlue. 
5. According to paragraph 3, what artificial intelligence stands out among the other present systems?

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Next time your boss asks you to work late and miss your band rehearsal or board game night, point them to a new study in the Journal of Vocational Behavior. Researchers have found that spending more time on a hobby can boost people’s confidence in their ability to perform their job well. Ciara Kelly at Sheffield University and colleagues recruited 129 hobbyists — from amateur climbers to improv comedians — to look at how the time spent on their hobbies shaped their work life. To begin with, the team measured the seriousness of each participant’s hobby, asking them to rate their agreement with statements like “I regularly train for this activity”, and also assessed how similar the demands of their job and hobby were. Then, each month for seven months, participants recorded how many hours they had dedicated to their activity, and completed a scale measuring their belief in their ability to effectively do their job, or their “self-efficacy”, in which they rated themselves on statements like “At work I am able to successfully overcome many challenges”.  The researchers found that when participants spent longer than normal doing their leisure activity, their belief in their ability to perform their job increased. But this was only the case when they had a serious hobby that was dissimilar to their job, or when their hobby was similar to their work but they only did it casually. When their hobby was both serious and similar to their job, then spending more time on it actually had a detrimental effect, decreasing their self-efficacy. Why might that be? To maintain a serious hobby, people need to invest significant psychological resources, so if the activity has the same kinds of demands as their work, they may be left drained and unable to perform as well at their job. But if their hobby is quite different from their career, it may not interfere in the same way but instead help them develop other knowledge and skills that can boost their confidence at work. Of course, the data don’t provide conclusive evidence about the direction of the effect. Still, the results suggest that companies may want to encourage employees to pursue interests outside of work, as long as those activities differ from their day-to-day tasks. And they also may give pause to those who dream of packing it all in and turning their hobby into a career.  
4. The word “self-efficacy” in paragraph 3 is closest in meaning to _______

Read the following passage and choose the best answer (A, B, C, D):
Children’s behaviour has worsened over the past five years, according to a survey of  teachers which found that a fifth thought girls were more likely to cause trouble than boys. The survey, published after teachers at a Lancashire school went on strike over discipline, found low-level disruption, including chatting and “horsing around”, was the biggest problem. Boys were more likely to be physically aggressive while girls tended to ostracise other pupils. The behaviour of boys was more of a challenge than that of girls but the actions of each sex had deteriorated, according to 56.5% of staff surveyed by the Association of Teachers and Lecturers (ATL).  Among male pupils the most challenging behaviour for teachers was physical aggression, such as pushing, spitting, kicking and hitting. A secondary teacher quoted in the survey said boys were usually aggressive with other pupils, while girls tended to call one another names. Teachers criticised a lack of role models in the home. A primary teacher said: “The boys are far more willing to be aggressive to adults, verbally and even physically. There don’t seem to be any parental boundaries set of what is an appropriate way to speak and deal with another adult.” Teachers at Darwen Vale high school, Lancashire, walked out over unruly pupil behaviour this month. They said children challenged them to fights and threatened to film lessons and post them online. The survey of more than 850 teachers, heads and other school staff found that more than 21% thought girls’ behaviour was more challenging than boys, compared with 68% who said male pupils caused more trouble. In schools that have excluded pupils, 57% said more boys and 5% said more girls had been excluded. A department head in a primary school told the survey, carried out in March, that “classes with a majority of boys tend to be louder, less co-operative and harder to teach”. Nearly half of the staff surveyed said boys’ bravado was behind their disruption. For girls, the most likely trigger was a break-up between friends. A primary school teacher from Bedfordshire said: "Boys are generally more physical and their behaviour is more noticeable. Girls often say nasty things, which end up disrupting the lesson just as much as the boys, as other children get upset and can’t focus on their work. They are usually the ones who refuse to comply with instructions." Some staff had noticed girls’ behaviour worsening.” A teaching assistant from Weston-super-Mare said: “Girls are definitely getting more violent, with gangs of girls in school who are getting worse than the gangs of boys.” The ATL annual conference in Liverpool on Monday is due to debate a motion expressing concern at increasing numbers of girls being excluded from secondary school.  Government figures for 2008-9 showed that boys represented 78% of the total number of permanent exclusions from schools in England. This proportion was unchanged from the year before. The ATL general secretary, Mary Bousted, said: "Staff get ground down daily by the chatting and messing around, which disrupts lessons for other pupils and takes the pleasure out of teaching. Even more worrying is the physical aggression, most often among boys but also among some girls, which puts other pupils and staff at risk. Schools need to have firm and consistent discipline policies and work with parents to keep schools and colleges safe places for pupils and staff alike." The education bill, now going through the Commons, will give teachers the right to search pupils for banned items and will remove the requirement to give parents a day’s notice of detention. The education secretary, Michael Gove, said the measures in the bill would “restore discipline” in the classroom.
4. According to paragraph 3, female pupils are described that _____________

Read the following passage and choose the best answer (A, B, C, D):
Light pollution is excessive, misdirected, or obtrusive artificial (usually outdoor) light. Too much light pollution has (1) __________effects on people. I washes out starlight in the night sky, disrupts ecosystems, has adverse health effects, and wastes energy. With respect to adverse health effects, many species, (2) ___________humans, are dependent on natural body cycles, and the production of melatonin, which are regulated by light and dark (e.g., day and night). If humans are exposed to light (3) ________sleeping, melatonin production can be affected. This can lead to sleep disorders and other health problems such as increased headaches, worker fatigue, medically defined stress, some forms of obesity due to lack of sleep and increased anxiety. And ties are being (4) ________ to a couple of types of cancer. There are also effects of glare on aging eyes. Heath effects are not only due to overillumination or excessive (5) ________of light over time, but also improper spectral composition of light

Read the following passage and choose the best answer (A, B, C, D):
If you go back far enough, everything lived in the sea. At various points in evolutionary history, enterprising individuals within many different animal groups moved out onto the land, sometimes even to the most parched deserts, taking their own private seawater with them in blood and cellular fluids. In addition to the reptiles, birds, mammals and insects which we see all around us, other groups that have succeeded out of water include scorpions, snails, crustaceans such as woodlice and land crabs, millipedes and centipedes, spiders and various worms. And we mustn’t forget the plants, without whose prior invasion of the land, none of the other migrations could have happened. Moving from water to land involved a major redesign of every aspect of life, including breathing and reproduction. Nevertheless, a good number of thoroughgoing land animals later turned around, abandoned their hard-earned terrestrial re-tooling, and returned to the water again. Seals have only gone part way back. They show us what the intermediates might have been like, on the way to extreme cases such as whales and dugongs. Whales (including the small whales we call dolphins) and dugongs, with their close cousins, the manatees, ceased to be land creatures altogether and reverted to the full marine habits of their remote ancestors. They don’t even come ashore to breed. They do, however, still breathe air, having never developed anything equivalent to the gills of their earlier marine incarnation. Turtles went back to the sea a very long time ago and, like all vertebrate returnees to the water, they breathe air. However, they are, in one respect, less fully given back to the water than whales or dugongs, for turtles still lay their eggs on beaches. There is evidence that all modern turtles are descended from a terrestrial ancestor which lived before most of the dinosaurs. There are two key fossils called Proganochelys quenstedti and Palaeochersis talampayensis dating from early dinosaur times, which appear to be close to the ancestry of all modern turtles and tortoise. You might wonder how we can tell whether fossil animals lived in land or in water, especially if only fragments are found. Sometimes it’s obvious. Ichthyosaurs were reptilian contemporaries of he dinosaurs, with
fins and streamlined bodies. The fossils look like dolphins and they surely lived like dolphins, in the water. With turtles it is a little less obvious. One way to tell is by measuring the bones of their forelimbs.
7. What does the word “they” in the last paragraph refer to?

Choose the best answer:
Would you mind _______ more clearly, please?

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 from 26 to 30.
In the year 1900, the world was in the midst of a machine revolution. (26) _____ electrical power became more ubiquitous, tasks once done by hand were now completed quickly and efficiently by machine. Sewing machines replaced needle and thread. Tractors replaced hoes. Typewriters replaced pens. Automobiles replaced horse-drawn carriages.
A hundred years later, in the year 2000, machines were again pushing the boundaries of (27) _____ was possible. Humans could now work in space, thanks to the International Space Station. We were finding out the composition of life thanks to the DNA sequencer. Computers and the world wide web changed the way we learn, read, communicate, or start political revolutions.
So what will be the game-changing machines in the year 2100? How will they (28) _____ our lives better, cleaner, safer, more efficient, and (29) _____ exciting?
We asked over three dozen experts, scientists, engineers, futurists, and organizations in five different disciplines, including climate change, military, infrastructure, transportation, and space exploration, about how the machines of 2100 will change humanity. The (30) _____ we got back were thought-provoking, hopeful and, at times, apocalyptic.

Question 27: .......................

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Thunderstorms, with their jagged bursts of lightning and roaring thunder, are actually one of nature’s primary mechanisms for transferring heat from the surface of the earth into the atmosphere. A thunderstorm starts when low-lying pockets of warm air from the surface of the earth begin to rise. The pockets of warm air float upward through the air above that is both cooler and heavier. The rising pockets cool as their pressure decreases, and their latent heat is released above the condensation line through the formation of cumulus clouds. What will happen with these clouds depends on the temperature of the atmosphere. In winter, the air temperature differential between higher and lower altitudes is not extremely great, and the temperature of the rising air mass drops more slowly. During these colder months, the atmosphere, therefore, tends to remain rather stable. In summer, however, when there is a high accumulation of heat near the earth’s surface, in direct contrast to the considerably colder air higher up, the temperature differential between higher and lower altitudes is much more pronounced. As warm air rises in this type of environment, the temperature drops much more rapidly than it does in winter; when the temperature drops more than 4 degrees Fahrenheit per thousand feet of altitude, cumulus clouds aggregate into a single massive cumulonimbus cloud, or thunderhead. In isolation, a single thunderstorm is an impressive but fairly benign way for Mother Earth to defuse trapped heat from her surface; thunderstorms, however, can appear in concert, and the resulting show, while extremely impressive, can also prove extraordinarily destructive. When there is a large-scale collision between cold air and warm air masses during the summer months, a squall line, or series of thunderheads, may develop. It is common for a squall line to begin when an advancing cold front meets up with and forces itself under a layer of warm and moist air, creating a line of thunderstorms that races forward at speeds of approximately forty miles per hour. A squall line, which can be hundreds of miles long and can contain fifty distinct thunderheads, is a magnificent force of nature with incredible potential for destruction. Within the squall line, often near its southern end, can be found supercells, long-lived rotating storms of exceptional strength that serve as the source of tornadoes.
6. The word “itself” in paragraph 3 refers to ________