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I will never talk to you again …… you apologize me ……… your being rude

 

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English is considered as one of our __________ languages.

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Money habits matter a lot in a relationship, even if you’re not married or living together, concludes Melissa A Curran, an associate professor at the University of Arizona, in a new study published in the Journal of Family and Economic Issues. That’s why she recommends being picky when it comes to dating. “Young adults should choose their romantic partner wisely,” Curran tells CNBC Make It. She and her colleagues assessed over 500 young twenty-somethings in committed relationships and had them rate their health and overall life satisfaction. She asked them questions related to their partners’ financial responsibility, such as, Do they spend within a budget? And, Do they usually pay off their credit cards in full? The researchers found that the more responsible the participants perceived their partners to be with money, the higher their own sense of well-being and the happier they were with their relationships. The opposite was also true. Participants who thought their partners were bad with money had a lower sense of well-being and felt less committed to the relationship. “This finding makes sense developmentally as the young adults are transitioning to adulthood,” says Curran. “It would make sense for them to draw upon romantic partners in terms of financial socialization agents.” By socialization agents, she means people who can teach and influence the participants on matters related to money. The idea is that the financial habits of whoever you’re dating can rub off on you. If your partner is bad with money, you might become bad with money too, which in turn affects your life overall, since the researchers also confirmed that your own financial habits definitely affect your well-being. For many young adults, parents are the most influential socialization agents. So, in this study, Curran also asked the participants about what their parents expected of them when it came to their finances. Did their parents, for example, expect them to track their spending? The researchers found that high expectations from an involved parent led the participants to perform better on a financial literacy test. But, unlike romantic partners, they did not seem to influence well-being. If you’re bothered by your significant other’s over-spending or general irresponsibility with money, Curran and her colleagues recommends talking things through. “Having discussions about finances and making financial decisions together helps couples
become closer and more satisfied with their relationships.”
4. According to paragraph 3, what can be generalized about the conclusion of the finding?

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While good grades are important and should be something every student strives for, they do not necessarily correlate with a student’s intelligence. Students should worry less about their grades and instead care more about retaining the content they are learning and gaining actual knowledge. David Thomas, a principal lecturer at ASU, said there are varying theories about intelligence. One of them is the entity theory of intelligence, which describes intelligence as being stable throughout someone’s life. Thomas said there are also people who think just the opposite, and that a person can become more intelligent throughout their life. While there are varying theories on what intelligence is and whether it can improve, you can gain knowledge throughout the course of your life. This principle should be the focus of education, not a person’s grades. Every student at ASU is preparing for a career and learning the necessary skills to do well in their desired industry. Getting an “A” on a test will not mean anything if you cannot apply the material you learned to real-life situations. Just because someone gets an “A” in a class or is in Barrett, the Honors College, it doesn’t define intelligence. Similarly, someone who gets a “D” in a class is not necessarily unintelligent, as there are other factors that play into grades. Take Bill Gates for example, a very wealthy and successful man who dropped out of Harvard University two years into his degree and later became the co-founder of Microsoft. He is intelligent, and yet he did not have a college degree when he started his company. Additionally, Thomas said motivation plays a big part in a person’s grades. A student with mastery-oriented motivation approaches a class with curiosity and an interest in the subject, whereas a student with performance-orientated motivation does so solely from a grade standpoint. If people spent the same amount of time working to ensure they retain important information as they did pulling all-nighters to cram for finals, they could become be more intelligent. Students should focus on developing their critical thinking and problemsolving skills rather than simply memorizing information for a test. A transcript only shows a student’s motivation, dedication and work ethic — not their personality, humor, work or life experiences. While grades still matter, we need to stop weighing our intelligence through grades and instead recognize that intelligence comes in all forms.
3. According to paragraph 2, what is NOT stated about the various theories on intelligence?

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The era of “smart cities”, controlled by an ecosystem of sensors, cameras and  algorithms, is fast approaching. In China, state media claim 500 are under construction. In Canada, Alphabet has plans for turning parts of Toronto into a timber-framed tech town as a prototype. Incremental steps are also making cities smarter. Last week, Transport for London announced plans to track Tube passengers through WiFi to monitor congestion. In the US, fast-food drive-throughs will trial number plates scanners to make ordering faster. Individually these services can improve daily life. Integrating them will create something more powerful than the sum of its parts.  Though convenience and safety are the end goals, serious questions about how city authorities will both store and share vast bodies of data must be answered. The fact that surveillance is built into key transport infrastructure will also make it increasingly difficult to avoid without disrupting daily life. The smart city risks creating a panopticon in the name of an easier and better life. The risks of anonymity disappearing will be increased by the use of different data sets, making it more likely that identifiable characteristics may appear. Closely linked to this is the question of data storage and sharing. The treasure trove of personal information will be a tempting target for hackers. This information might also be used by law enforcement, feeding into the existing dangers of mass surveillance and profiling, as is already the case in China.  These concerns have long been levelled at social media and internet-enabled home appliances. Smart city surveillance can be even more insidious. Users can avoid Facebook or hardware such as Alexa. Avoiding basic infrastructure will be near impossible without seriously affecting day-to-day life. TfL has put up signs warning customers of the WiFi tracking, yet the only choice is between tracking and having no signal. Reports on the facial recognition at airports in America suggest that avoiding being automatically scanned will be tough as well. As these systems become more closely enmeshed, avoiding snooping will become increasingly tricky.  The inevitable rise of smart cities is not inherently negative. Harnessing the power of technology and data can potentially help urban environments adapt to challenges such as climate change and overcrowding. Politicians, programmers and academics must work to ensure that does not come at the cost of all-seeing, 24-hour surveillance. 
7. Which of the following statements is TRUE, according to the passage?

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You like history, so Viet Nam National Museum of History is a _____ place.

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When I tell people about the idea of moving out, many people’s reaction is like, “what do your parents say?” because they assume the parents would not like their children to leave them. Well I don’t know if my parents like it but I can tell you my parents support and respect my decision. They think it is good for me to try and live on my own and then I would know it is the best to stay with my family. The most important reason for independent living is to save the travelling time to work. It used to take me one hour fifteen minutes to travel to work from my previous living place. From my new apartment, it just takes me thirty minutes so I saved forty-five minutes’ traveling time. I don’t have to get up so early and I save two-third of my traveling cost. It does not only save my time to travel for work but also from most of the places in Hong Kong. In addition, I gain my personal space and freedom by independent living. I make my own decision all the time, I do not have to say whether I would go home for dinner, I can invite my friends to come up and stay late. Of course, there are some trade-offs in living on your own. If you want to rent an apartment, there are lots of preparatory work to do. You have to keep visiting the apartments to search for your ideal one. You have to negotiate with the landlord about the price, furniture inclusion, who is responsible for the maintenance of the furniture and equipment. My experience was that after we moved into the apartment, it was not until the kitchen cupboard was soaked with water that we found out there was water leakage in the kitchen sink. Money is the main issue in living on your own. You have to be responsible for all the expenses, for example, the rent, electricity, gas, water, telephone, internet bills, etc.  Therefore, you’ve got to be well prepared and save up for your bills. Although I find my transportation time much shorter, the saved time is spent on other things, such as cooking and some other household chores. I think preparing and cooking the food do occupy a significant portion of my time, therefore I always try to make simple meals. On the other hand, I have to regularly tidy up my apartment and wash my clothes, so it doesn’t really save much of my time after all. Now everything is settled down, I’m getting used to my new life and I am enjoying it. I feel that moving out makes it easier for me to strike a balance between my work, my social life, my study and my family. It may be troublesome but it may worth  
3. The word "trade-offs" in the passage is closest in meaning to ____

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It’s extremely important for kids of middle childhood to continue, or to start to lead a healthy lifestyle, including eating nutritious meals as well as getting plenty of exercise and adequate sleep every day. These positive health habits will help children grow strong, stay healthy, and decrease the likelihood that they will become obese. Childhood obesity rates have increasing dramatically in recent years. According to the Centers for Disease Control, in 2004, 18.8% of school-aged children were obese, versus 4% of children 30 years before in 1974. Children’s skyrocketing rate of obesity is worrisome because it greatly increases children’s risk for remaining obese in adulthood, which in turn raises their risk for heart disease, stroke, cancer, diabetes, and premature death as adults. Obese children may also develop associated health problems during the middle childhood stage, such as high blood pressure, high cholesterol levels, and respiratory problems. Obesity can also set the stage for problems with self esteem, depression, anxiety and social ostracism, and/or being victimized by bullies Healthy diet and adequate exercise are important in preventing Type II diabetes in childhood as well as obesity. Diabetes is a metabolic disease in which the body cannot properly metabolize the sugars from food. Because the body cannot metabolize sugars, the sugars accumulate in the bloodstream instead and ultimately stress children’s kidneys, heart, circulatory system, and eyes. Insulin, which is created in the pancreas, is the chemical that breaks down blood sugar. In Type II diabetes, the body does not produce enough insulin to deal with all the sugars coming into the body. This medical diagnosis used to be called “adult-onset diabetes” because the disorder primarily affected adults with poor eating and activity habits. Today, however, this illness is now diagnosed in America’s children far more than in adults. It is now referred to as “Type II diabetes”, to reflect this shift in prevalence. In contrast to the many youth in America who overeat and don’t get enough exercise, other children become obsessed with over-controlling their food intake and with exercising too much. With the constant barrage of perfect, photoshopped bodies in the media today, many children are feeling pressure at younger and younger ages to imitate those images. Children as young as 6 are reporting that they are trying to lose weight by dieting. Overemphasis on extreme thinness can put children at risk for poor self-esteem, unhealthy exercise patterns, and eating disorders such as anorexia and bulimia. Children who embrace healthy eating and exercise habits during middle childhood will have a much easier time maintaining a healthy lifestyle through adolescence and adulthood than individuals who try to make the shift later in life. Teaching children to habitually eat moderate portion sizes and to choose healthy foods in preference to junk foods becomes increasingly important as children begin to spend more time away from home and gain more independence over their food and activity choices. Even though parents have less control over their children’s eating habits during middle childhood than when children were younger, it remains vital that parents continue to reinforce children’s healthy habits whenever possible. 
1. Which of the following best serves as the title for the passage?

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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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According to airline industry statistics, almost 90 percent of airline accidents are survivable or partiallysurvivable. But passengers can increase their chances of survival by learning and following certain tips. Experts say that you should read and listen to safety instruction before take off and ask questions if you have uncertainties. You should fasten your seat belt low on your hips and as tightly as possible. Of course, you should also know how the release mechanism of your belt operates. During takeoffs and landings, you are advised to keep your feet flat on the floor. Before take off, you should locate the nearest exit and an alterative exit and count the rows of seats between you and the exits so that you can
reach them in the dark if necessary. In the event that you are forewarned of a possible accident, you should put your hands on your ankles and keep your head down until the planes comes to a complete stop. If smoke is present in the cabin, you should keep your head low and cover your face with napkins, towels, or clothing. If possible, wet these for added protection against smoke inhalation. To evacuate as quickly as possible, follow crew commands and do not take personal belongings with you. Do not jump on escape slides before they are fully inflated, and when you jump, do so with your arms and legs extended in front of you. When you get to the ground, you should move away from the plane as quickly as possible, and smoke near the wreckage
6. It can be inferred from the passage that people are more likely to survive fires in aircrafts if they

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Sophia is a humanoid robot developed by Hong Kong-based company Hanson Robotics. She has been designed to learn and adapt to human behavior and work with humans, and has been interviewed around the world. In October 2017, she became a Saudi Arabian citizen, the first robot to receive citizenship of a country. According to herself, Sophia was activated on April 19, 2015. She is modeled after actress Audrey Hepbum,and is known for her human-like appearance and behavior compared to previous robotic variants. According to manufacturer, David Hanson, Sophia has artificial intelligence, visual data processing and facial recognition. Sophia also imitates human gestures and facial expressions and is able to answer certain questions and to make simple conversations on predefined topics (e.g. on the weather). The robot uses voice recognition technology from Alphabet Inc. (parent company of Google) and is designed to get smarter over time. Sophia’s intelligence software is designed by SingularityNET. The AI program analyses conversations and extracts data that allows her to improve responses in the future. It is conceptually similar to the computer program ELIZA, which was one of the first attempts at simulating a human conversation. Hanson designed Sophia to be a suitable companion for the elderly at nursing homes, or to help crowds at large events or parks. He hopes that she can ultimately interact with other humans sufficiently to gain social skills. Sophia has been interviewed in the same manner as a human, striking up conversations with hosts. Some replies have been nonsensical, while others have been impressive, such as lengthy discussions with Charlie Rose on 60 Minutes. In a piece for CNBC, when the interviewer expressed concerns about robot behavior, Sophia joked that he had “been reading too much Elon Musk, and watching too many Hollywood movies”. Musk tweeted that Sophia could watch The Godfather and suggested “What’s the worst that could happen?”. On October 11, 2017, Sophia was introduced to the United Nations with a brief conversation with the United Nations Deputy Secretary-General, Amina J. Mohammed. On October 25, at the Future Investment Summit in Riyadh, she was granted Saudi Arabian citizenship, becoming the first robot ever to have a nationality. This attracted controversy as some commentators wondered if this implied that Sophia could vote or marry, or whether a deliberate system shutdown could be considered murder. Social media users used Sophia’s citizenship to criticize Saudi Arabia’s human rights record. 
1. The passage mainly discusses________

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Whether a species is endangered—meaning at risk of extinction—depends on which definition you use. The International Union for Conservation of Nature’s Red List of Threatened Species classifies an animal as endangered when its numbers in the wild have dropped so low that it’s at “extremely high risk” of extinction. Meanwhile, the United States’ Endangered Species Act of 1973 takes into consideration any destruction to a species’ habitat, whether it has been over-consumed, any disease or predation that threaten it, whether any other man-made factors put it in danger, and what policies currently exist to protect it. When members of the public or a state agency propose to the U.S. Fish & Wildlife Service or the National Marine Fisheries Service that a species be listed as endangered under the law, research and management plans are formed to help those species survive. It is illegal under the Endangered Species Act to capture, hunt, shoot, or otherwise harm an animal that’s listed as endangered. Sometimes, federal agencies decide that although a species could be considered endangered, other species are higher priorities. In those cases, the animal or plant gets limited protections. One animal whose numbers have increased through conservation is the bald eagle. There were only about 500 bald eagles in the continental United States in the 1960s because of pesticides that damaged the shells of their eggs. Conservation efforts including captive breeding programs, habitat protection, and a ban on the insecticide DDT helped the bald eagle’s numbers soar back into the thousands. Another is the giant panda, which was declared no longer endangered in 2016 thanks to 50 years of efforts to save it. U.S. Rep. John Dingell, who wrote the Endangered Species Act, argued that “only natural extinction is part of natural order.” Scientists believe that 227 species - including the grizzly bear, the peregrine falcon and the gray wolf - were saved from extinction in the first 33 years of the law’s existence. Still, critics argue that the act is expensive and ineffective because it protects so many species. Several federal courts have heard and rejected arguments that the Endangered Species Act is unconstitutional, and members of Congress have tried to weaken the law in small ways.
3. The word “propose” in 2 paragraph is closest in meaning to _______

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Do you know that your place on the family ladder may have certain effects on the sort of person you grow up to be? You may be the only child, the eldest, youngest or (1) _______ one; you may be the youngest of three boys or the eldest girl with a younger brother and sister. All the different combinations of relationships will have helped to (2) __________ you the person you are. The number of years between your siblings and you also helps to shape your character. Knowing such details about your best friend or loved one (3) _______ also tell you about the type of friend or partner he needs. For example, a boy with a younger sister would normally get along much better (4) ______ a girl who has an older brother than with a girl who has a younger brother. Similarly, if your girlfriend is the oldest in her family, she would probably be domineering. Fortunately for all of us, family psychology is not (5) _______ accurate. There are always exceptions to the rule. Most important of all, we should always judge people according to who they are, not the relatives they have

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She did a funny little curtsy which Josh and Silver couldn't help ____ at.

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You’ll be able to purchase high-quality emotions online. Emotion-sharing experiences  are the latest fad in 2045. Imagine your friend at Glastonbury can post a photo on Instagram and with it comes bundled a faint twinkling of what she was feeling right there in that moment, so you too can share emotionally in her social experience.  Recently, techniques for direct brain stimulation, like opt genetics, have made it possible to not only read but also write information into single neurons. At the moment data transfer rates are still very slow, the best we can do is a few bits per second, but this could well increase to kilobits or maybe reach broadband speeds by 2045. This means the range of human perception could expand beyond its current design limitations. One could foresee a new and extraordinary world where there is a virtual marketplace for trading high quality emotions – where artists looking for a particularly high strength brew of melancholy, or actors needing to channel regret or compassion for their next play, could purchase emotions online.  Our cities will be made from living, dynamic materials that respond to the environment. In 30 years, tall buildings made of glass and twisted steel will be seen as relics from a bygone era, in the same way we think now of 1970s concrete tower blocks: ugly, outdated and unfit for contemporary purpose. The urban environment of 2045 blends architecture with living materials that are mouldable, adaptable, responsive and disposable.  Entirely new synthetic life forms, or biological machines, made of engineered living cells from bacteria, fungi and algae will grow and evolve with the changing needs of a building’s inhabitants. They breathe in pollutants, clean wastewater, and use sunlight to make useful chemicals, energy, heat and vibrant vertical gardens. We will start to see a convergence between biology and technology, to the point where there is no longer a perceptible difference between the two. Today, synthetic biology labs are looking at the full diversity of what nature has to offer and using this to mix, match and edit genomes to design synthetic life forms. Right now, this field is just getting started and the science of synthetic biology is going to be tougher than most will admit.  We will use invisibility cloaks to “disappear” ugly objects. Invisibility has forever been a tantalizing prospect. The key to cloaking lies in the way the electromagnetic spectrum  (including visible light) interacts with objects. The human eye picks up electromagnetic radiation that falls and scatters from objects and we perceive this as light. In recent decades, scientists figured out using mathematics that it might just be possible to imagine a new class of artificial materials made of intricate tiny features with light bending properties. They named them metamaterials.  Using nanotechnology engineering, scientists have since shown cloaking actually works – in principle at least, for a narrow range of colours and only from certain viewing angles. The future applications of cloaking are highly uncertain and will likely be determined by the fads and social contagion of the time. They may be used in everything from novelty gimmicks to making unsightly construction sites and power stations seemingly ‘disappear’.   
5. The word “perceptible” in the third paragraph is closest in meaning to ______

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Going to a restaurant shouldn’t be your excuse to eat unhealthy foods. Follow these tips and not only will you enjoy your meal more, you’ll feel satisfied and happy when you’re done. First, ask for it your way. Dining out is no time to be a meek consumer, notes Michael F. Jacobson, Ph.D., executive director of the Center for Science in the Public Interest (CSPI) and coauthor of the book Restaurant Confidential. “You need to be an assertive consumer by asking for changes on the menu,” he says. For instance, if an item is fried, ask for it grilled. If it comes with French fries, ask for a side of veggies instead. Ask for a smaller portion of the meat and a larger portion of the salad; for salad instead of coleslaw; baked potato instead of fried. “Just assume you can have the food prepared the way you want it,” says Dr. Jacobson. “Very often, the restaurant will cooperate.” Second, order A Salad before ordering anything else on the menu. Scientists at Pennsylvania State University found that volunteers who ate a big veggie salad before the main course ate fewer calories overall than those who didn’t have a first-course salad, notes Novick. However, remember: Salads Shouldn’t Be Fatty. This is a vegetable course-keep it tasty but healthy. That means avoiding anything in a creamy sauce (coleslaw, pasta salads, and potato salads), and skipping the bacon bits and fried noodles. Instead, load up on the raw vegetables, treat yourself to a few well-drained marinated vegetables (artichoke hearts, red peppers, or mushrooms), and for a change, add in some fruit or nuts. Indeed, fruits such as mango, kiwi, cantaloupe, and pear are often the secret ingredient in four-star salads.  
3. What does the word “those" in the third paragraph refer to?

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You will never eat there at the weekend unless you have made a reservation.

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I said that I remembered _____with him in a handicraft village, but he said I was mistaken.

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New York city is well-known _______ the Statue of Liberty.

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Like the revolutions that preceded it, the Fourth Industrial Revolution has the potential to raise global income levels and improve the quality of life for populations around the world. To date, those who have gained the most from it have been consumers able to afford and access the digital world; technology has made possible new products and services that increase the efficiency and pleasure of our personal lives. Ordering a cab, booking a flight, buying a product, making a payment, listening to music, watching a film or playing a game — any of these can now be done remotely. In the future, technological innovation will also lead to a supply-side miracle, with long-term gains in efficiency and productivity. Transportation and communication costs will drop, logistics and global supply chains will become more effective and the cost of trade will diminish, all of which will open new markets and drive economic growth. At the same time, as the economists Erik Brynjolfsson and Andrew McAfee have pointed out, the revolution could yield greater inequality, particularly in its potential to disrupt labor markets. As automation substitutes for labor across the entire economy, the net displacement of workers by machines might exacerbate the gap between returns to capital  and returns to labor. On the other hand, it is also possible that the displacement of workers by technology will, in aggregate, result in a net increase in safe and rewarding jobs. We cannot foresee at this point which scenario is likely to emerge, and history suggests that the outcome is likely to be some combination of the two. However, I am convinced of one thing — that in the future, talent, more than capital, will represent the critical factor of production. This will give rise to a job market increasingly segregated into “low-skill/low-pay” and “highskill/high-pay” segments, which in turn will lead to an increase in social tensions. In addition to being a key economic concern, inequality represents the greatest societal concern associated with the Fourth Industrial Revolution. The largest beneficiaries of innovation tend to be the providers of intellectual and physical capital — the innovators, shareholders and investors — which explains the rising gap in wealth between those dependent on capital versus labor. Technology is therefore one of the main reasons why incomes have stagnated, or even decreased, for a majority of the population in high-income countries: the demand for highly skilled workers has increased while the demand for workers with less education and lower skills has decreased. The result is a job market with a strong demand at the high and low ends, but a hollowing out of the middle. This helps explain why so many workers are disillusioned and fearful that their own real incomes and those of their children will continue to stagnate. It also helps explain why middle classes around the world are increasingly experiencing a pervasive sense of dissatisfaction and unfairness. A winnertakes-all economy that offers only limited access to the middle class is a recipe for democratic malaise and dereliction.  
4. What will happen if the number of workers is replaced by machine?

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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 ________