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 .
A recent (1)....... of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (2)........ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on  offer  leads  to  a  recognized  qualification.  Also,  be  realistic  in your (3).......... If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (4)........ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience.  "I  think  the  teacher’s  role  is  important.  It's  so  nice  to  have  somebody  give  you  a/an (5) ........... ”.
(3)................................
 

Interest is the sum charged for borrowing money for a fixed period of time. Principal is the term used for the money that is borrowed, and the rate of interest is the percent per year of the principal charged for its use. Most of the profits for a bank are derived from the interest that they charge for the use of their own or their depositor’s money.
All problems in interest may be solved by using one general equation that may be stated as follows:
Interest = Principal X Rate X Time
Any one of the four quantities – that is, interest, principal, rate, or time – may be found when the other three are known. The time is expressed in years. The rate is expressed as a decimal fraction. Thus, 6 percent interest means six cents charged for the use of $1 of principal borrowed for one year. Although the time may be less than, equal to, or greater than one year, most applications for loans are for periods of less than one year. For purpose of computing interest for short periods, the commercial year or 360 days is commonly used, but when large sums of money are involved, exact interest is computed on the basis of 365 days.

Most applications for loans are for.............

Choose the word which is stresses differently from the rest: renovate, domesticate, initiate, eliminate

Choose the word which is stresses differently from the rest: economic, experience, entertainment, introduction

Quite different from storm surges are the giant sea waves called tsunamis, which derive their name from the Japanese expression for “high water in a harbor.” These waves are also referred to by the general public as tidal waves, although they have relatively little to do with tides.
Scientists often referred to them as seismic sea waves, far more appropriate in that they do result from undersea seismic activity.
Tsunamis are caused when the sea bottom suddenly moves, during an underwater earthquake or volcano for example, and the water above the moving earth is suddenly displaced. This sudden shift of water sets off a series of waves. These waves can travel great distances at speeds close to 700 kilometers per hour. In the open ocean, tsunamis have little noticeable amplitude, often no more than one or two meters. It is when they hit the shallow waters near the coast that they increase in height, possibly up to 40 meters.
Tsunamis often occur in the Pacific because the Pacific is an area of heavy seismic activity.
Two areas of the Pacific well accustomed to the threat of tsunamis are Japan and Hawaii. Because the seismic activity that causes tsunamis in Japan often occurs on the ocean bottom quite close to the islands, the tsunamis that hit Japan often come with little warning and can, therefore, prove disastrous. Most of the tsunamis that hit the Hawaiian Islands, however, originate thousands of miles away near the coast of Alaska, so these tsunamis have a much greater distance to travel and the inhabitants of Hawaii generally have time for warning of their imminent arrival.
Tsunamis are certainly not limited to Japan and Hawaii. In 1755, Europe experienced a calamitous tsunami, when movement along the fault lines near the Azores caused a massive tsunami to sweep onto the Portuguese coast and flood the heavily populated area around Lisbon. The greatest tsunami on record occurred on the other side of the world in 1883 when the Krakatoa volcano underwent a massive explosion, sending waves more than 30 meters high onto nearby Indonesian islands; the tsunami from this volcano actually traveled around the world and was witnessed as far away as the English Channel.

The possessive “their” refers 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 questions.

      Contrary to popular belief, one does not have to be a trained programmer to work online. Of course, there are plenty of jobs available for people with high-tech computer skills, but the growth of new media has opened up a wide range of Internet career opportunities requiring only a minimal level of technical expertise. Probably one of the most well-known online job opportunities is the job of Webmaster. However, it is hard to define one basic job description for this position. The qualifications and responsibilities depend on what tasks a particular organization needs a Webmaster to perform.

      To specify the job description of a Webmaster, one needs to identify the hardware and software the website the Webmaster will manage is running on. Different types of hardware and software require different skill sets to manage them. Another key factor is whether the website will be running internally or externally (renting shared space on the company servers). Finally, the responsibilities of a webmaster also depend on whether he or she will be working independently, or whether the firm will provide people to help. All of these factors need to be considered before one can create an accurate webmaster job description.

      Webmaster is one type of Internet career requiring in-depth knowledge of the latest computer applications. However, there are also online jobs available for which traditional skills remain in high demand. Content jobs require excellent writing skills and a good sense of the web as a “new media”.

      The term “new media” is difficult to define because it compasses a constantly growing set of new technologies and skills. Specifically, it includes websites, email, internet technology, CD-ROM, DVD, streaming audio and video, interactive multimedia presentations, e-books, digital music, computer illustration, video games, virtual reality, and computer artistry.

      Additionally, many of today’s Internet careers are becoming paid-by-the-job professions. With many companies having to downsize in tough economic items, the outsourcing and contracting of freelance workers online has become common business practice. The Internet provides an infinite pool of buyers from around the world with whom freelancers can contract their services. An added benefit to such online jobs is that freelancers are able to work on projects with companies outside their own country.

      How much can a person make in these kinds of careers? As with many questions related to today’s evolving technology, there is no simple answer. There are many companies willing to pay people with Internet skills salaries well over $70,000 a year. Generally, webmasters start at about $30,000 per year, but salaries can vary greatly. Freelance writers working online have been known to make between $40,000 to $70,000 a year.

According to the passage, all of the followings are TRUE except ___________.

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.
In the past, the process of choosing a career was a much simpler matter than it is today. Aboy often followed in his father’s footsteps. His sister learned the household skills that (1)..... her to become a wife and mother. Nowadays young people grow up in a much freer society (2)........they enjoy almost unlimited career opportunities. In recent years, there (3)..... an enormous increase in the kinds of vocations from which it is possible to choose. In addition, many of the barriers to career opportunity that existed only a few decades ago, such as (4).......... based on sex or religion or ethnic origins, are (5)............... disappearing.
(2)..................

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

"Before the 1960s, Singapore was essential a trading nation. Since (1)….. , it has developed a more (2)…. economy and has become an important financial, trade, and transportation center. Singapore has (3)….. banks, insurance, and finance companies, as (4) …..  as a stock exchange. Tourism is also important to the (5)…. of Singapore.
 There is (6)…. unemployment in Singapore. The country’s annual income per capita (per person) is one of the (7) …. in Asia. The government of Singapore plays a major role in the country’s economy. For example, it (8)….. what benefits, such as vacation time and sick leave, must be (9)….for workers by employers. It also operates an employment agency to help people find jobs, and it provides (10)…..  for retired workers."

4 , as (4) …..  as a stock exchange.

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On the tiny island of Flores, east of Bali and midway between Asia and Australia, the scientists have discovered the remains of a small, hobbit-like species of humans. These people grew no larger than the modern three-year-old child. They lived about 18,000 years ago and are completely different species of human.
This discovery has taught scientists a lot about the human species. This remarkable discovery shows that the human species is more varied and flexible in its ability to adapt than previously thought. These hobbit-like people join a short list of other type of humans that lived with modern humans.
The researchers believe that these hobbits evolved from a normal size, human population that reached Flores around 840,000 years ago. One likely explanation is that, over thousands of years, the species became smaller because the environmental conditions favored a smaller body size. The dwarfing of mammals on islands occurs frequently. Islands limit food supply and predators and species compete for the same environmental space. Survival would depend on minimizing energy requirements.a

According to the passage, why does a smaller size help species survive under certain condition?

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You might be surprised to know that bicycles have existed for less than two hundred years. Though the earliest comes from a sketch said to be from 1534 and attributed to Gian Giacomo, there are several early but unverified claims for the invention of the modem bicycle. No one is sure who invented this popular two- wheeled machine, but it was probably either the German Karl von Drais, in 1817, or the American W K Clarkson, in 1819. The early models didn't look much like the bicycles of today. The front wheel was much bigger than the back one, and also there weren't any pedals - riders had to move themselves forward by pushing their feet against the ground. Pedals finally arrived in the 1840s, and in 1879 an Englishman named Henry Lawson had the idea of connecting them to the back wheel with a chain. Gears, which made things much easier for those cycling uphill, first appeared in the 1890s.
There are now approximately one billion bicycles in the world - more than twice the total number of cars - and they are the main form of transport in some developing countries. They have to compete with cars on the streets of all the world’s cities, and the two forms of transport don't always mix well. In London in 2005, for example, over 300 cyclists were either killed or seriously injured in accidents involving cars. Even though bicycles are much more environmentally friendly than cars, most governments don't do much to encourage people to ride rather than drive. In China, which is famous for having a huge number of bicycles (about 200 million), the authorities in the city of Shanghai even banned cycling for a while in 2003.
Cycling is on the rise is the United Kingdom, and the number of annual journeys made by bike in London has increased 50% over the last five years. Experts say there is a mixture of reasons for this boom: concerns about the environment, the desire to keep fit, and also the fact that cycling is often not only cheaper but also quicker than travelling by car.
However, although one in three British adults owns a bicycle, they still don't use them nearly as much as they could. Bikes are used for a mere 2% of journeys in the UK, while the figure for the Netherlands is an impressive 27%.
Cycling is becoming more popular as a competitive sport, and the most famous race is of course the three-week Tour de France, which takes place every July. American Lance Armstrong won it every year from 1999 to 2005 - one of the greatest individual sporting achievements of all time.

In the Netherlands, what percentage of journeys are made by bicycle?

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

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions:
Public holidays in the United Kingdom, commonly referred to as bank holidays, are days where most businesses and non – essential services are closed although an increasing number of retail businesses (especially the larger ones) do open on some of the public holidays. There are restrictions on trading on Sundays and Christmas Day. Four public holidays are common to all countries of the United Kingdom. These are: New Year's Day, the first Monday in May, Christmas Day, and Boxing Day. Some banks open on some bank holidays. In Scotland, while New Year's Day and Christmas Day are national holidays, other bank holidays are not necessarily public holidays, since the Scots instead observe traditional local customs and practice for their public holidays. In Northern Ireland, once again, bank holidays other than New Year's
Day and Christmas Day are not necessarily public holidays. Good Friday and Christmas Day are common law holidays, except in Scotland, where they are bank holidays. In Scotland the holiday on 1 January (or 2 January if 1 January is Sunday) is statutory, and 25 December is also a statutory holiday (or 26 December if Christmas Day falls on a Sunday). Boxing Day is a holiday traditionally celebrated  the day following Christmas Day, when servants and tradesmen would receive gifts, known as a "Christmas box", from their bosses or employers. Today, Boxing Day is the bank holiday that generally takes place on 26 December. And 28 December only is given if Boxing Day is Saturday.
Like Denmark, the United Kingdom has no national day holiday marked or celebrated for its formal founding date. Increasingly, there are calls for public holidays on the patron saints' days in England, Scotland and Wales. An online petition sent to the Prime Minister received 11,000 signatures for a public holiday in Wales on St. David's Day; the Scottish Parliament has passed a bill creating a public holiday  on St. Andrew's Day although it must be taken in place of another public holiday; campaigners in England are calling for a bank holiday on St. George's Day; and in Cornwall, there are calls for a public holiday on St. Piran's Day.

Which of the following statements is wrong about the U.K.?

Being aware of one's own emotions - recognizing and acknowledging feelings as they happen - is at the very heart of Emotional Intelligence. And this awareness encompasses not only moods but also thoughts about those moods. People who are able to monitor their feelings as they arise are less likely to be ruled by them and are thus better able to manage their emotions.
Managing emotions does not mean suppressing them; nor does it mean giving free rein to every feeling. Psychologist Daniel Goleman, one of several authors who have popularized the notion of Emotional Intelligence, insisted that the goal is balance and that every feeling has value and significance. As Goleman said, "A life without passion would be a dull wasteland of neutrality, cut off and isolated from the richness of life itself." Thus, we manage our emotions by expressing them in an appropriate manner. Emotions can also be managed by engaging in activities that cheer us up, soothe our hurts, or reassure us when we feel anxious.
Clearly, awareness and management of emotions are not independent. For instance, you might think that individuals who seem to experience their feelings more intensely than others would be less able to manage them. However, a critical component of awareness of emotions is the ability to assign meaning to them - to know why we are experiencing a particular feeling or mood. Psychologists have found that, among individuals who experience intense emotions, individual differences in the ability to assign meaning to those feelings predict differences in the ability to manage them. In other words, if two individuals are intensely angry, the one who is better able to understand why he or she is angry will also be better able to manage the anger.
Self-motivation refers to strong emotional self-control, which enables a person to get moving and pursue worthy goals, persist at tasks even when frustrated, and resist the temptation to act on impulse. Resisting impulsive behavior is, according to Goleman, "the root of all emotional self- control."
Of all the attributes of Emotional Intelligence, the ability to postpone immediate gratification and to persist in working toward some greater future gain is most closely related to success - whether one is trying to build a business, get a college degree, or even stay on a diet. One researcher examined whether this trait can predict a child's success in school. The study showed that 4-year-old children who can delay instant gratification in order to advance toward some future goal will be "far superior as students" when they graduate from high school than will 4-year-olds who are not able to resist the impulse to satisfy their immediate wishes.

The word "soothe" in paragraph 2 could be best replaced by ..........

Read the passage carefully and choose the correct answer.

Vietnam is a densely-populated and developing country that in the last 30 years has had to recover from the ravages of war. Substantial progress was achieved from1986 to 1997 in moving forward from an extremely low level of development and significantly reducing poverty.

Since 2001, Vietnamese authorities have reaffirmed their commitment to economic liberalization and international integration. They have moved to implement the structural reforms needed to modernize the economy and to produce more competitive, export-driven industries…

Vietnam's membership in the ASEAN Free Trade Area (AFTA) and entry into force of the US-Vietnam Bilateral Trade Agreement in December 2001. have led to even more rapid changes in Vietnam's trade and economic regime. Vietnam's exports to the US doubled in 2002 and again in 2003.

Vietnam joined the WTO (World Trade Organization) in January 2007, following over a decade long negotiation process. This should provide ail important boost to the economy and should help to ensure the continuation of liberalizing reforms.

Vietnam is working to create jobs to meet the challenge of a labor force that is growing by more than one million people every year. Vietnamese authorities have tightened monetary and fiscal policies to stem high inflation. Hanoi is targeting an economic growth rate of 7. 5-8% during the next five years.

Vietnam's economy is _______.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
In the late 1960’s, many people in North America turned their attention to environmental problems and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a cluster of tall buildings in a city often overburdens public transportation and parking lot capacities.
Skyscrapers are also lavish consumers, and waster, of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York City raised the peak daily demand for electricity by 120,-000 kilowatts- enough to supply the entire city of Albany, New York, for a day.
Glass-walled skyscrapers can be especially wasteful. The heat loss (or gain) through a wall of half-inch plate glass is more than ten times that through a typical masonry wall filled with insulation board. To lessen the strain on heating and air- conditioning equipment, builders of skyscrapers have begun to use double glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain. However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings.
Skyscrapers put a severe strain on a city’s sanitation facilities, too. If fully occupied, the two World Trade Center towers in New York City would alone generate 2.25 million gallons of raw sewage each year-as much as a city the size of Stamford, Connecticut, which has a population of more than 109,000.
Skyscrapers also interfere with television reception, block bird flyways, and obstruct air traffic. In Boston, in the late 1960’s some people even feared that shadows from skyscrapers would kill the grass on Boston Common.
Still, people continue to build skyscrapers for all the reasons that they have always built them – personal ambition, civic pride, and the desire of owners to have the largest possible amount of rentable space.

The author raises issues that would most concern which of the following groups?

The Robots Are Doing the Thinking

Some robots may take care of the dishes, do your laundry, keep the house clean, or even go to the store to do your shopping. Robots that use artificial intelligence are the ones that a lot of people are holding out for. Not only will these robots be able to take care of (1)__________, but they will be able to learn as well.

There are some types of robots that already use a form of artificial intelligence called “swarm intelligence”. As a(n) (2)___________ of how this works, scientists have created underwater robots that will be used to repair coral reefs that have been damaged. What these robots do is work together to rebuild damaged reefs. As they (3)__________, each one knows what has been done in one area of a reef and can help build other areas or build onto something that another robot has done. Working together, the robots create a new reef that can then be (4)__________ to grow and thrive on its own.

Amazon, the major electronic commerce company, has recently come (5)_________ an ingenious idea. Instead of having a package delivered to a customer via delivery truck, Amazon will send out flying drones that will bring a package to a person’s house for delivery almost immediately. 

(3)__________

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.
            MAKING THE MOST OF YOUR TIME
These days we are under pressure to increase the amount of work we can achieve in the shortest time. The pace of life threatens to leave many of us behind, and (1)........ of this pressure we spend time looking for short-cuts in our working lives. However, these time-saving measures may actually cause more problems than they solve.
Some organisations seem to expect staff to work more than the usual eight hours, without recognising the fact that tiredness causes people to make silly mistakes and leads to (2)......... working practices. Try setting clear (3)......... in your everyday work, however, you must be careful that these are not unrealistic and can be achieved within the working day. We tend to (4)......... people who can multi-task because we think they are working hard – but do all the electronic gadgets they use increase their efficiency in the long run? Instead, they may distract them from the task in hand and cause a loss of concentration. Maybe (5)........... with every email or mobile phone call immediately is not the best use of anyone’s time. To sum up, my advice is to keep everything simple, and prioritise tasks - you will become happier at work – and so will your boss!
(3)...............................
 

It's called 42 - the name taken from the answer to the meaning of life, from the science fiction series The Hitchhiker's Guide to the Galaxy. 42 was founded by French technology billionaire Xavier Niel, whose backing means there are no tuition fees and accommodation is free. Mr Niel and his co-founders come from the world of technology and start-ups, and they are trying to do to education what Facebook did to communication and Airbnb to accommodation.
Students at 42 are given a choice of projects that they might be set in a job as a software engineer - perhaps to design a website or a computer game. They complete a project using resources freely available on the Internet and by seeking help from their fellow students, who work alongside them in a large open-plan room full of computers. Another student will then be randomly assigned to mark their work.
The founders claim this method of learning makes up for shortcomings in the traditional education system, which they say encourages students to be passive recipients of knowledge. "Peer-to-peer learning develops students with the confidence to search for solutions by themselves, often in quite creative and ingenious ways."
Like in computer games, the students are asked to design and they go up a level by completing a project. They graduate when they reach level 21, which usually takes three to five years. And at the end, there is a certificate but no formal degree. Recent graduates are now working at companies including IBM, Amazon, and Tesla, as well as starting their own firms.
"The feedback we have had from employers is that our graduates are more apt to go off and find out information for themselves, rather than asking their supervisors what to do next," says Brittany Bir, chief operating officer of 42 in California and a graduate of its sister school in Paris. Ms Bir says 42's graduates will be better able to work with others and discuss and defend their ideas - an important skill in the “real world” of work. "This is particularly important in computer programming, where individuals are notorious for lacking certain human skills," she says. 
But could 42's model of teacher less learning work in mainstream universities? Brittany Bir admits 42's methods do not suit all students. "It suits individuals who are very disciplined and self-motivated, and who are not scared by having the freedom to work at their own pace," she says.

Which of the following is TRUE according to the passage?

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

Which of the following would be the best title for the passage?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Line Europeans who arrived in the Americas, the first American Indians were immigrants. Because Indians were nomadic hunters and gatherers, they probably arrived in search of new hunting grounds from Asia when they crossed the ice-covered Bering Strait to Alaska. Anthropologists estimate that the entire Indian population north of Mexico was slightly greater than 1,020,000 when the first settlers arrived from Europe. Although Native Americans belonged to one geographic race, their cultures and languages were only marginally similar, and by and large, they had different ways of life. Nomadic migrations required Indians to construct shelters that did not need to be transported, but could be easily erected from the materials found in their new location.
Eastern Woodland Indian tribes lived in bark-covered wigwams that were shaped like cones or domes. The frame for the hut was made of young trees firmly driven into the ground, and then bent overhead to tie together with bark fibers or strings of animal hides. Sheets and slabs of bark were attached to the frame to construct the roof and walls, leaving an opening to serve as a door and to allow smoke to escape. The Iroquois in north eastern regions built longhouses that were more spacious than wigwams because five to a dozen families lived under one roof. During the winter, they plastered clay to the poles of the frame to protect the inhabitants from wind and rain.
Pueblo Indians who lived in the southwest portion of the United States in northern Arizona and New Mexico constructed elaborate housing with several stories and many rooms. Each family unit had only one room, and their ancestors dug shelters in the walls of cliffs and canyons. The ground story of a Pueblo dwelling had no doors or windows in order to prevent enemies from entering. The next level was set back the width of one room, and the row of rooms above it was set back once again, giving their houses the appearance of a terrace Pueblos used ladders to climb to the upper levels and pulled them in when all family members returned for the night.
Indians living in deserts used sandstone and clay as construction materials. Those who lived in the valleys of rivers even made bricks of clay with wood chips to add strength and to prevent the clay from cracking. To make roofs, Pueblos tied logs together to make rafters and laid them across the two outside walls. On top of the rafters, layers of tree branches, sticks, grass, and brush created a solid roof to preclude the water from leaking inside. Pueblo dwellings were dark because windows were often not large enough to allow much light.

What does the passage mainly discuss?

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

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