Choose the best answer:
Recycling is a good way of ___________ the environment.

 

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It is natural for young people to be critical of their parents at times and to blame them for most of the misunderstandings between them. They have always complained, more or less justly, that their parents are out of touch with modern ways; that they are possessive and dominant; that they do not trust their children to deal with crises; that they talk too much about certain problems, and that they have no sense of humor, at least in parent-child relationships. I think it is true that parents often underestimate their teenage children and also forget how they themselves felt when they were young. Young people often irritate their parents with their choices in clothes and hairstyles, in entertainers and music. This is not their motive. They feel cut off from the adult world into which they have not yet been accepted. So they create a culture and society of their own. Then, if it turns out that their music or entertainers of vocabulary or clothes or hairstyles irritate their parents, this gives them additional enjoyment. They feel they are superior, at least in a small way, and that they are leaders in style and taste. Sometimes you are resistant and proud because you do not want your parents to approve of what you do. If they approve, it looks as if you are betraying your own age group. But in that case, you are assuming that you are the underdog; you cannot win; but at least you keep your honor. This is a passive way of looking at things. It is natural enough after long years of childhood, when you were completely under your parents’ control. But it ignores the fact that you are now beginning to be responsible for yourself. If you plan to control your life, cooperation can be part of that plan. You can charm others, especially your parents, into doing things the way you want. You can impress others with your sense of responsibility and initiative, so that they will give you the authority to do what you want to do.  
1. The author of the passage is primarily addressing __________

In the mid - nineteenth century, the United States had tremendous natural resources that could be exploited in order to develop heavy industry. Most of the raw materials that are valuable in the manufacture of machinery, transportation facilities, and consumer goods lay ready to be worked into wealth. Iron, coal, and oil - the basic ingredients of industrial growth - were plentiful and needed only the application of technical expertise, organizational skill, and labor.

One crucial development in this movement toward industrialization was the growth of the railroads. The railway network expanded rapidly until the railroad map of the United States looked like a spider's web, with the steel filaments connecting all important sources of raw materials, their places of manufacture, and their centers of distribution. The railroads contributed to the industrial growth not only by connecting these major centers, but also by themselves consuming enormous amounts of fuel, iron, and coal.

Many factors influenced emerging modes of production. For example, machine tools, the tools used to make goods, were steadily improved in the latter part of the nineteenth century - always with an eye to speedier production and lower unit costs. The products of the factories were rapidly absorbed by the growing cities that sheltered the workers and the distributors. The increased urban population was nourished by the increased farm production that, in turn, was made more productive by the use of the new farm machinery. American agricultural production kept up with the urban demand and still had surpluses for sale to the industrial centers of Europe.

The labor that ran the factories and built the railways was recruited in part from American farm areas where people were being displaced by farm machinery, in part from Asia, and in part from Europe. Europe now began to send tides of immigrants from eastern and southern Europe - most of whom were originally poor farmers but who settled in American industrial cities. The money to finance this tremendous expansion of the American economy still came from European financiers for the most part, but the American were approaching the day when their expansion could be financed in their own " money market"

The word" ran" in the paragraph 4 is closest in meaning to ________

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions:
Foot racing is a popular activity in the United States. It is seen not only as a competitive sport but also as a way to exercise, to enjoy the camaraderie of like-minded people, and to donate money to a good cause. Though serious runners may spend months training to compete, other runners and walkers might not train at all. Those not competing to win might run in an effort to beat their own time or simply to enjoy the fun and exercise. People of all ages, from those of less than one year (who may be pushed in strollers) to those in their eighties, enter into this sport. The races are held on city streets, on college campuses, through parks, and in suburban areas, and they are commonly 5 to 10 kilometers in length.
The largest foot race in the world is the 12-kilometer Bay to Breakers race that is held in San Francisco every spring. This race begins on the east side of the city near San Francisco Bay and ends on the west side at the Pacific Ocean. There may be 80,000 or more people running in this race through the streets and hills of San Francisco. In the front are the serious runners who compete to win and who might finish in as little as 34 minutes. Behind them are the thousands who take several hours to finish. In the back of the race are those who dress in costumes and come just for fun. One year there was a group of men who dressed like Elvis Presley, and another group consisted of firefighters who were tied together in a long line and who were carrying a fire hose. There was even a bridal party, in which the bride was dressed in a long white gown and the groom wore a tuxedo. The bride and groom threw flowers to bystanders, and they were actually married at some point along the route.

The main purpose of this passage is to     .

Choose the best answer:
Both fossil fuel _______ non-renewable resources are very important to our life.

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Perfectly smart adults feel intimidated by numbers and aren’t ashamed to say, “I hate math.” The new book “Math Art” could help change that by making the dreaded topic relevant and accessible to naturalists, artsy types, the philosophically inclined, and committed calculators alike. It illuminates an old lesson your math teachers probably tried to convey when you were a kid: Math dominates our lives even while we try with all our might to ignore it. In Math Art, released in April, science writer Ornes examines creative works inspired by math. It’s an aesthetically pleasing book with a delightfully tactile cover and satisfyingly thick and glossy pages that make it as fun to flip through as a fashion magazine. Chapters are dedicated to different concepts like pi, the golden ratio, equations in nature, and hyperbolic geometry. All of which may sound scary to the uninitiated but gain appeal when illustrated through sculpture, crochet, and painting. As Ornes explains in the introduction, math art isn’t new. Since ancient times, humans have visualized math in creative works. He argues that what is new is the mutual recognition that mathematicians and artists now show each other, increasingly gathering together at events dedicated to the intersection of aesthetics and numbers. “This is art by way of math and math by way of art, beauty at the crossroads,” Ornes writes.  His exploration begins with pi, the irrational mathematical constant 3.14159, plus some, ad infinitum. Pi, the ratio of the circumference of a circle to its diameter, represents mystery itself. Because the sequence never repeats, pi hints at the vastness of the universe. “It speaks to a world without bounds, since its digits go on forever,” Ornes explains. Pi is used for calculations in math and physics, and employed by math artist John Sims to make music, videos, drawings, paintings, quilts, clothing, and stories. Sims created and taught a math curriculum for students at the Ringling College of Art and Design in Sarasota, Florida, and has spent much of his career at the intersection of math and creativity. In Ornes’ book, he explains how he’s also used this fascination to connect with other people he might not otherwise meet, such as the Amish quilters who joined him to make pi quilts with each colored panel representing a number in the mathematical sequence.  
5. The word “It” in paragraph 3 refers to _____

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Most people have heard about how PTSD can unravel a person. Fewer have heard about posttraumatic growth, the process that lifted Curry out of his despair and into his new role as a leader in the veteran community. The term - defined as “positive change that occurs as a result of the struggle with highly challenging life crises” - was coined in the mid-1990s by Richard Tedeschi, PhD, and Lawrence Calhoun, PhD, after studying how people develop wisdom. They identified five specific ways people can grow after a crisis. First, their relationships strengthen. One woman diagnosed with breast cancer, for example, said she realized her relationships “are the most important things you have.” Bereaved parents told Tedeschi and Calhoun that losing a child had made them more compassionate. Second, they discover new paths and purposes in life. Sometimes these are related to a particular survivor mission. One interviewee became an oncology nurse after losing her child to cancer. Other times, the crisis becomes the catalyst for a more general reconsideration of priorities, as Christine discovered when she started attending The Dinner Party in the aftermath of her mother’s death. Third, the trauma allows them to find their inner strength. The common thread among those Tedeschi and Calhoun studied is a “vulnerable yet stronger” narrative. This paradoxical outlook defined the attitude of a rape survivor who admitted the world seemed more dangerous after the assault, but that, at the same time, she felt more resilient as a result of the inner strength she’d built. Fourth, their spiritual life deepens. That could mean they renew their faith in God, or it could mean they grapple with existential questions more broadly, coming to know certain deep truths about the world or themselves, as one interviewee did after his spinal-cord surgery. Finally, they feel a renewed appreciation for life. Rather than taking for granted a stranger’s kindness or the vivid colors of autumn leaves, they savor the small moments of beauty that light up each day. The difference between those who are able to grow from adversity and those who are stymied lies in what Tedeschi and Calhoun call “deliberate rumination” or introspection. The participants they studied spent a lot of time trying to make sense of their painful experiences, reflecting on how the events changed them. Doing so helped them make the life changes associated with posttraumatic growth.  
6. Which of the following statements is TRUE, according to the passage?

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In 1959 Xerox created the first plain paper copy machine. It was one of the most  successful products ever. The company name Xerox grew into a verb that means “to copy,” as in “Bob, can you Xerox this for me?” Around 50 years later, the same thing happened to Google. Their company name grew into a verb that means “to do an internet search.” Now everyone and their grandma knows what it means to Google it.  Unlike Xerox, Google wasn’t the first company to invent their product, not by a long shot. Lycos released their search engine in 1993. Yahoo! came out in 1994. AltaVista began serving results in 1995. Google did not come out until years later, in 1998. Though a few years difference may not seem like much, this is a major head start in the fast moving world of tech. So how did Google do it? How did they overtake their competitors who had such huge leads in time and money? Maybe one good idea made all the difference.  There are millions and millions of sites on the internet. How does a search engine know which ones are relevant to your search? This is a question that great minds have been working on for decades. To understand how Google changed the game, you need to know how search engines worked in 1998. Back then most websites looked at the words in your query. They counted how many times those words appeared on each page. Then they might return pages where the words in your query appeared the most. This system did not work well and people often had to click through pages and pages of results to find what they wanted.  Google was the first search engine that began considering links. Links are those blue underlined words that take you to other pages when you click on them. Larry Page, cofounder of Google, believed that meaningful data could be drawn from how those links connect. Page figured that websites with many links pointing at them were more important than those that had few. He was right. Google’s search results were much better than their rivals. They would soon become the world’s most used search engine.  It wasn’t just the great search results that led to Google becoming so wellliked. It also had to do with the way that they presented their product. Most of the other search engines were cluttered. Their home pages were filled with everything from news stories to stock quotes. But Google’s homepage was, and still is, clean. There’s nothing on it but the logo, the search box, and a few links. It almost appears empty. In fact, when they were first testing it, users would wait at the home page and not do anything. When asked why, they said that they were, “waiting for the rest of the page to load.” People couldn’t imagine such a clean and open page as being complete. But the fresh design grew on people once they got used to it. 
2. Which statement does the author NOT mention in the passage?

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I started snowboarding in my late 20s and, knowing the dangers involved, my main aim has always been to get myself safely down the mountain in one piece. However, last year, I began to feel that my lack of courage was preventing me from improving. So I booked myself on the Snowcamp course in the town of Bourg-Saint-Maurice in the French Alps. There were 14 of us on the course and we stayed in a cheap guesthouse just outside the town. It was a basic-looking building made of local wood. There were strict rules about recycling our rubbish and all the electricity came from a nearby windmill. The facilities, however, went well beyond what I had expected for the price. There was a log fire, a heated boot room, fine balcony views and a menu that any chef would be proud of. Snowcamp was a good mix of holiday and group learning. Locations for lessons were chosen daily according to the snow conditions. Then we were put into three groups, depending on what skills people wanted to work on. Most of the time, I stayed on the main slopes. The teachers encouraged me to increase my speed and I even did some jumps. After a few days, a teacher called Johno persuaded me to take on a bigger challenge and try the deeper snow. The first 20 seconds of the lesson were fantastic, but then it got difficult. I kept sinking and then having to dig myself out. After 40 minutes, I felt like crying with tiredness and anger but I continued pushing myself and, when I got back on to the main slopes, I suddenly found everything far easier than before. It had been worth all the pain!  
2. How did Pascal feel about the guesthouse he stayed in?

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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.  
7. The word “they” in paragraph 4 refers to _____

Rewrite the sentence:
The polluted water results in the death of many aquatic animals and plants.

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There is still no consensus about how the Neanderthals were driven to extinction,  leaving our Homo sapien ancestors without any competition. The disappearance of the native European Neanderthals is odd partly because their shorter, stockier bodies must have made them better able to withstand the colder temperatures that prevailed when their cousins from Africa entered Europe. With a smaller surface area the Neanderthal body would have been able to retain more heat. The once common assumption that the key was the inferior vocal abilities of the Neanderthal has since been disproved by research on the Neanderthal hyoid bone, located in the throat. The larger skull capacity and brain is another respect in which they do not seem to have been inferior.  It was once thought that proof of a superior intellect was to be found in the narrower Homo sapien stone tools known as “blades”, which were assumed to be more efficient than the broader “flakes” used by the Neanderthals. In a number of important respects, including durability, this idea has proved to be unfounded. However, the blades would have been more effective as tips for throwing spears whereas the stone flakes would have been limited to the kind of thrusting spears the Neanderthals are believed to have used. This could have combined with the greater agility of the Homo sapiens to give them a distinct advantage in hunting on open terrain. Crucial in this respect were the larger canals in the Homo sapien inner ear, providing a more acute sense of balance, in addition to the longer limbs and lighter build. The Neanderthal technique of hiding and lying in wait for passing animals ceased to be viable when the dense forests of Europe began to recede. After a period of co-existence with their cousins, the Neanderthals were slowly eradicated.
4. The Neanderthals were wiped out ________________

Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions:
A recent study shows that an unequal share of household chores is still the norm in many households, despite the fact that many more women now have jobs. In a survey of 1,256 people ages between 18 and 65, men said they contributed an average of 37% of the total housework, while the women estimated their share to be nearly double that, at 70%. This ratio was not affected by whether the woman was working or not.
When they were asked what they thought was a fair division of labour, women with jobs felt that housework should be shared equally between male and female partners. Women who did not work outside the home were satisfied to perform 80% - the majority of the household work - if their husbands did remainder. Research has shown that, if levels increase beyond these percentages, women become unhappy and anxious, and feel they are unimportant.
After marriage, a woman is reported to increase her household workload by 14 hours per week, but for men the amount is just 90 minutes. So the division of labour becomes unbalanced, as a man's share increases much less than the woman's. It is the inequality and loss of respect, not the actual number of hours, which leads to anxiety and depression. The research describes housework as thankless and unfulfilling. Activities included in the study were cooking, cleaning, shopping, doing laundry, washing up and childcare. Women who have jobs report that they feel overworked by these chores in addition to their professional duties. In contrast, full-time homemakers frequently anticipate going back to work when the children grow up. Distress for this group is caused by losing the teamwork in the marriage.

All activities mentioned in the passage are household chores EXCEPT     

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It’s important to be able to articulate your dream job. Not just for personal reasons,  but also for when you’re asked about it in interviews. But, how can you even begin to describe your ideal job, especially to someone who’s clearly going to be judging your response? Just picking a place to start is a head-scratcher.  First, let’s talk about what you’re good at doing, or your strengths. It’s likely you’ve already had the chance to talk about this topic a bit during the interview, so it makes for a nice transition. Highlight the skills that you enjoy using most, not just the ones you’re a superstar at. This is about your dream job, so don’t shy away from mentioning any that you want to grow as well.  Think big picture for this. What drew you to your industry? What’s something you did as a kid that’s actually found its way into your work? What is it about your career that keeps you engaged? Weave that in. Giving a sense of what your career values are will give the interviewer an idea about what motivates you; it’s a good way to bring the focus back to the company you’re interviewing for. It also adds some extra complexity to your answer. You’re not just saying, “I want an interesting job that I’m good at.” I mean, that’s nice, but this is your dream job we’re talking about! Don’t pigeonhole yourself with anything that official. Instead, give the hiring manager a more nuanced response by covering your skills, interests, and values. He or she will get the chance to learn more about you—and you have more flexibility to line up your career goals and the position you’re applying for. That’s a win-win. 
1. Which best serves as the title for the passage?

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Political and economic reforms launched in 1986 have transformed the country from  one of the poorest in the world, with per capita income around US $100, to lower middle income status within a quarter of a century with per capita income of around US$ 2,100 by the end of 2015.  Vietnam’s per capita GDP growth since 1990 has been among the fastest in the world, averaging 5.5 percent a year since 1990, and 6.4 percent per year in the 2000s. Vietnam’s economy continued to strengthen in 2015, with estimated GDP growth rate of 6.7 percent for the whole year.  The Vietnamese population is also better educated and has a higher life expectancy than most countries with a similar per capita income. The maternal mortality ratio has dropped below the upper-middle-income country average, while under-five mortality rate has fallen by half, to a rate slightly above that average. Access to basic infrastructure has also  improved substantially. Electricity is now available to almost all households, up from less than half in 1993. Access to clean water and modern sanitation has risen from less than 50 percent of all households to more than 75 percent.  Vietnam’s Socio-Economic Development Strategy (SEDS) 2011-2020 gives attention to structural reforms, environmental sustainability, social equity, and emerging issues of macroeconomic stability. It defines three “breakthrough areas”: promoting human resources/skills development (particularly skills for modern industry and innovation), improving market institutions, and infrastructure development. In addition, the five-year Socio-Economic Development Plan 2011-2015 focused on three critical restructuring areas - the, banking sector, state-owned enterprises and public investment that are needed to achieve these objectives. The recent draft of the SEDP 20162020 acknowledges the slow progress of the reform priorities of the SEDP 2011-2015. With agriculture still accounting for almost half the labor force, and with significantly lower labor productivity than in the industry and services sectors, future gains from structural transformation could be substantial. The transformation from state to private ownership of the economy is even less advanced. The state also wields too much influence in allocating land and capital, giving rise to heavy economy wide inefficiencies. So, adjusting the role of the state to support a competitive private sector-led market economy remains a major opportunity. This will be important for enhancing productivity growth which has been stagnating for a long time.
4. According to the passage, nearly _________ of the households did NOT get access to clean water in 2015.

Read the following passage and choose the best answer (A, B, C, D):
It is natural for young people to be critical of their parents at times and to blame them for most of the misunderstandings between them. They have always complained, more or less justly, that their parents are out of touch with modern ways; that they are possessive and dominant; that they do not trust their children to deal with crises; that they talk too much about certain problems, and that they have no sense of humor, at least in parent-child relationships. I think it is true that parents often underestimate their teenage children and also forget how they themselves felt when they were young. Young people often irritate their parents with their choices in clothes and hairstyles, in entertainers and music. This is not their motive. They feel cut off from the adult world into which they have not yet been accepted. So they create a culture and society of their own. Then, if it turns out that their music or entertainers of vocabulary or clothes or hairstyles irritate their parents, this gives them additional enjoyment. They feel they are superior, at least in a small way, and that they are leaders in style and taste. Sometimes you are resistant and proud because you do not want your parents to approve of what you do. If they approve, it looks as if you are betraying your own age group. But in that case, you are assuming that you are the underdog; you cannot win; but at least you keep your honor. This is a passive way of looking at things. It is natural enough after long years of childhood, when you were completely under your parents’ control. But it ignores the fact that you are now beginning to be responsible for yourself. If you plan to control your life, cooperation can be part of that plan. You can charm others, especially your parents, into doing things the way you want. You can impress others with your sense of responsibility and initiative, so that they will give you the authority to do what you want to do.  
8. In discussing parent-child relationships, the author seems _________

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Botswana, officially the Republic of Botswana, is a country in southern Africa that shares borders with South Africa, Namibia and Zimbabwe. The capital, Gaborone, (1) _______ on the Notwane River in the South east of Botswana. The Kalahari Desert covers more than 70% of Botswana. The Kalahari isn’t a true desert because it rains more each year there than in most (2) _______ deserts. Despite this, Botswana is a dry country. When it does rain, the rain is often heavy and there are floods. Botswana is a popular tourist destination, with people from all over the world coming to see its amazing animals. During the seasonal floods, the land becomes a lush animal habitat. The wide variety of wildlife (3) __________ elephants and lions. Many visit Chobe National Park to see its 70,000 elephants, (4) __________ are the largest of all living elephants. The grassland and river valleys are home to giraffes, cheetahs, hyenas and wild dogs. The baobab tree, an icon of the African savannah, plays an important role in Botswana culture and nearly every part of it is useful. For example, it (5) __________ used to make rope and people pick the leaves to make soup

Find opposite:
Among friends again, we may be happy to confide our innermost secrets.

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Do you think computer games are just for kids? Then you should think again. You might be surprised to learn that the game industry now (1)_________ more money than Hollywood. From 2009 to 2012, the U.S. video game industry increased in size by more than 9 percent - four times the growth rate of the U.S. economy during the same period. (2)___________a family buys a new PC , all they really want to do is to play games. It is hardly surprising that video gaming has become one of the most popular (3)___________of entertainment today. One study even showed that some mental disorder patients who play games requiring physical interaction while standing on a balance board displayed improvement afterwards. A good game is like a good film; it will hold your (4)__________, capture your imagination and play with your emotions. The big (5)__________ , however, is that watching a movie is a passive task, you have to say in how the plot develops or which characters dominate the story. With computer games, you direct the action and that is what makes them so exciting

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After World War II drew to a close in the mid-20th century, a new conflict began.  Known as the Cold War, this battle pitted the world’s two great powers–the democratic, capitalist United States and the communist Soviet Union–against each other. By the mid1950s, the U.S.-Soviet Cold War had worked its way into the fabric of everyday life in both countries, fueled by the arms race and the growing threat of nuclear weapons, wide-ranging espionage and counter-espionage between the two countries, war in Korea and a clash of words and ideas carried out in the media. These tensions would continue throughout the space race, exacerbated by such events as the construction of the Berlin Wall in 1961, the Cuban missile crisis of 1962 and the outbreak of war in Southeast Asia. Space exploration served as another dramatic arena for Cold War competition. On October 4, 1957, a Soviet R-7 intercontinental ballistic missile launched Sputnik (Russian for “traveler”), the world’s first artificial satellite and the first man-made object to be placed into the Earth’s orbit. Sputnik’s launch came as a surprise, and not a pleasant one, to most Americans. In the United States, space was seen as the next frontier, a logical extension of the grand American tradition of exploration, and it was crucial not to lose too much ground to the Soviets. In addition, this demonstration of the overwhelming power of the R-7 missile– seemingly capable of delivering a nuclear warhead into U.S. air space–made gathering intelligence about Soviet military activities particularly urgent.  Beginning in the late 1950s, space would become another platform for the competition, as each side sought to prove the superiority of its technology, its military firepower and–by extension–its political-economic system.
4. According to paragraph 2, why did most Americans harbour an unanimous displease toward Soviet’s achievement?

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:
The difference between the nuclear family and the extended family is that a nuclear family refers to a single basic family unit of parents and their children, whereas the extended family refers to their relatives such as grandparents, in-laws, aunts and uncles, etc. In many cultures, and particularly indigenous societies, the latter is the most common basic form of social organization. A nuclear family is limited, according to Kristy Jackson of Colorado State University, to one or two parents (e.g. a father and mother) and their own child, or children, living together in a single house or other dwellings. In anthropology, they only must be related in this fashion; there is no upper or lower limit on the number of children in a nuclear family.
The extended family is a much more nebulous term, but in essence refers to kin or relations not covered by the above definition. In historical Europe and Asia as well as in Middle Eastern, African, and South American Aboriginal cultures, extended family groups were typically the most basic unit of social organization. The term can differ in specific cultural settings, but generally includes people related in age or by lineage. Anthropologically, the term “extended family” refers to such a group living together in a household, often with three generations living together (grandparents, parents, and children) and headed in patriarchal societies by the eldest man or by some other chosen leadership figure. However, in common parlance, the term “extended family” is often used by people simply to refer to their cousins, aunts, uncles, and so on, even though they are not living together in a single group.
Historically, most people in the world have lived in extended family groupings rather than in nuclear families. This was even true in Europe and in the early United States, where multiple generations often lived together for economic reasons. During the 20th century, average income rose high enough that living apart as nuclear families became a viable option for the vast majority of the American population. In contrast, many indigenous societies and residents of developing countries continue to have multiple generations living in the same household. The rise of the nuclear family in the modern West does not necessarily mean that family arrangements have stabilized, either. The rapid growth in single-parent households, for instance, also represents a substantial change in the traditional nuclear family. More couples are also choosing not to have children at all.

According to the passage, single-parent households     .