Read the passage and choose the best answer to compete each of the statements that follow
The hippopotamus is the third largest land animal, smaller only than the elephant and the rhinoceros. Its name comes from two Greek words which mean "river horse". The long name of this animal is often shortened to the easier to handle term "hippo."
The hippo has a natural affinity for the water. It does not float on top of the water; instead, it can easily walk along the bottom of a body of water. The hippo commonly remains underwater for three to five minutes and has been known to stay under for up to half an hour before coming up for air.
In spite of its name, the hippo has relatively little in common with the horse and instead has a number of interesting similarities in common with the whale. When a hippo comes up after a stay at the bottom of a lake or river, it releases air through a blowhole, just like a whale. In addition, the hippo resembles the whale in that they both have thick layers of blubber for protection and they are almost completely hairless.

It can be inferred from the passage that the rhinoceros is_____________

 

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

"Do you want to take part in the battle to save the world’s wildlife? “Animal Watch” is a book which will (1)….. you in the fight for survival that (2)….  many of our endangered animals and show how they struggle on the (3)…. of extinction. As you enjoy the book’s 250 pages and over 150 coloured photographs, you will have the (4)…..  of knowing that part of your purchase money is being used to help animals (5)…. . From the comfort of your armchair, you will be able to observe the world’s animals close-up and explore their habitats. You will aỉso discover the terrible results of human greed for land, flesh and skins.
 “Animal Watch” is packed with fascinating facts. Did you know that polar bears cover their black noses (6)…. their paws so they can hunt their prey in the snow without being seen, for example? Or that for each orangutan which is captured, one has to die?
 This superb (7)…. has so (8)….. Britain’s leading wildlife charity that it has been chosen as Book of the Year, a (9)….. awarded to books which are considered to have made a major contribution to wildlife conservation. You will find “Animal Watch” at a special low introductory at all good bookshops, but hurry while (10)….. last."

6. Did you know that polar bears cover their black noses (6)…. their paws so they can hunt their prey in the snow without being seen, for example?

Read the following passage and choose the best answer for each blank.

The World Wide Fund for Nature (WWF) is an international (26) _____- governmental organization for the (27) _____, research, and restoration of the environment. The organization was (28) _____ as a charitable trust on September 11, 1961, in Morges, Switzerland, under the name World Wildlife Fund. It was an initiative of Julian Huxley and Max Nicholson.It is the world's largest independent conservation organization with over 5 million (29) _____ worldwide, working in more (30) _____ 90 countries, supporting 100 conservation and environmental projects around the world. It is a charity, with (31) ____ 9% of its funding coming from voluntary (32) ___ by private individuals and businesses.The group says its mission is "to halt and reverse the (33) _____ of our environment". Currently, much of its work focuses on the conservation of three biomes that contain most of the world's biodiversity: forests, freshwater ecosystems, and oceans and coasts. Among other issues, it is also concerned (34) _____ endangered species, pollution, and climate change. The organization (35) ____ more than 20 field projects worldwide. In the last few years, the organization set up offices and operations around the world.

(29) _____

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. 
Exactly 50 years ago, humanity stepped foot on the surface of the Moon for the first time. It was a miracle, and one made so powerful because it was so very unlikely. It was hailed as an incredible success. But the chance of failure was such that authorities had to prepare for the possibility of losing the astronauts. Those preparations offer a humbling insight into how risky that mission was, and how high the stakes were. Probably the most potent document from those preparations is the speech that would have been used to hail the bravery of the astronauts as they were left to their death on the Moon.
It was written to announce to the world that the astronauts had been lost, and that the Moon mission was a failure. After it was read, the two astronauts would be given a ceremony something like the burial at sea, but one entirely without precedent. The document was hidden for many years – unused, it was "quietly tucked away into the record" after the astronauts returned home, as the National Archive that now holds it notes. But over time it became public, after being revealed by the man who wrote it, and is now available for the public to read.
It was prepared in the case that the astronauts and their moon lander failed to get back to the main craft that was floating around in the Moon's orbit ready to bring them home, and contained Neil Armstrong and Buzz Aldrin's colleague Michael Collins. In that case, it was most likely that those pioneering explorers would not lose their lives in a single spectacular moment. Instead, they would most likely be stranded, stuck 250,000 miles from Earth with no way of getting back home. "If they couldn't get back safely, they'd have to be abandoned on the moon, left to die there," speechwriter William Safire said in 1999. "The men would either have to starve to death or commit suicide."
In the end, and despite some very anxious moments, the crew would explore the lunar surface and come back down safely. That meant that, instead of announcing their loss, Nixon could instead share in the astronaut's success. In one of the most famous moments of the mission, he spoke to them in a phone call that was beamed around the world. He recognised the triumph of their achievement, and wished them safety for their return.

Which of the following could be the main topic of the passage?

Choose the best answer

The World Wide Fund for Nature (WWF) is an international (1) ____ governmental organization for the (2) ____, research, and restoration of the environment. The organization was (3) ____ as a charitable trust on September 11, 1961, in Morges, Switzerland, under the name World Wildlife Fund. It was an initiative of Julian Huxley and Max Nicholson. It is the world's largest independent conservation organization with over 5 million (4) ____ worldwide, working in more (5) ____ 90 countries, supporting 100 conservation and environmental projects around the world. It is a charity, with (6) ____ 9% of its funding coming from voluntary, (7) ____ by private individuals and businesses.

The group says its mission is "to halt and reverse the (8) ____ of our environment". Currently, much of its work focuses on the conservation of three biomes that contain most of the world's biodiversity: forests, freshwater ecosystems, and oceans and coasts. Among other issues, it is also concerned (9) ____ endangered species, pollution, and climate change. The organization (10) ____ more than 20 field projects worldwide. In the last few years, the organization set up offices and operations around the world.

(3) ____

Read the following passage and mark the letter A. B. C or D your answer sheet to indicate the correct answer to each of the questions.

CAN ANIMALS TALK?

In 1977, a young Harvard graduate named Irene Pepperberg brought a one-year-old African gray parrot into her lab, and attempted something very unusual. At a time when her fellow scientists thought that animals could only communicate on a very basic level, Irene set out to discover what was on a creature's mind by talking to it. The bird, named Alex, proved to be a very good pupil.

Scientists at the time believed that animals were incapable of any thought. They believed that animals only reacted to things because they were programmed by nature to react that way, not because they had the ability to think or feel. Any pet owner would probably disagree. Pepperberg disagreed, too, and started her work with Alex to prove them wrong.

Pepperberg bought Alex in a pet store. She let the store's assistant pick him out because she didn't want other scientists saying later that she'd deliberately chosen an especially smart bird for her work. Most researchers thought that Pepperberg's attempt to communicate with Alex would end in failure.

However, Pepperberg's experiment did not fail. In fact, over the next few years, Alex learned to imitate almost one hundred and fifty English words, and was even able to reason and use those words on a basic level to communicate. For example, when Alex was shown an object and was asked about its shape, color, or material, he could label it correctly. He could understand that a key was a key no matter what its size or color, and could figure out how the key was different from others.

Pepperberg was careful not to exaggerate Alex's success and abilities. She did not claim that Alex could actually “use” language. Instead, she said that Alex had learned to use a two-way communication code. Alex seemed to understand the turn-taking pattern of communication.

In paragraph 3, "deliberately" 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 questions. 
      The reason women appear to be at greater risk of developing Alzheimer’s disease than men might be due to a number of genetic, anatomical and even social influences, researchers have suggested.
      Recent figures show about 65% of those with living with dementia in the UK are women, with a similar statistic seen in the US for Alzheimer’s disease, while dementia is the leading cause of death for women in England. Alzheimer’s disease is only one of the types of dementia, but the most common form. While one explanation is that dementia risk increases with age, and women have longer life expectancies than men, new research suggests there might be more to the matter, including that protein tangles found within neurons and linked to Alzheimer’s disease might spread differently in women’s brains than men’s.
      The study, presented at the Alzheimer’s Association International Conference in Los Angeles by researchers from Vanderbilt University and which has not yet been peer-reviewed, used scans from a method called positron emission tomography. That allowed them to look at the way clumps of a protein called tau were spread in the brains of 123 men and 178 women without cognitive problems, as well as 101 men and 60 women with mild cognitive problems – although not yet diagnosed with Alzheimer’s disease. Cognitively normal older people often have small amounts of tau in certain areas of their brain.
      From the data the team could build maps showing which areas of the brain show similar signals relating to tau in the scans, suggesting they are somehow connected. “Based on that we kind of try to reconstruct the pattern of spread,” Dr Sepideh Shokouhi, who is presenting the research, told the Guardian. “It is kind of like reconstructing a crime scene.” The team says the results suggest these maps look different in women and men, suggesting tau might be able to spread more rapidly across the female brain.
     Other research presented at the conference – and also not yet peer reviewed – added weight to the idea that there might be differences between men and women that affect dementia risk. Research by scientists at the University of Miami has revealed a handful of genes and genetic variants appear to be linked to Alzheimer’s disease in just one biological sex or the other. While the actual importance of these factors has yet to be unpicked, and the study only looked at white participants, the team says it underscores that there could be a genetic reason for differences in the risk of dementia in men and women, and the way it develops.

The following are the reasons for Alzheimer’s disease, EXCEPT ____________.

The Sun today is a yellow dwarf star. It is fueled by thermonuclear reactions near its center that convert hydrogen to helium. The Sun has existed in its present state for about four billion six hundred million years and is thousands of times larger than the Earth.
By studying other stars, astronomers can predict what the rest of the Sun's life will be like.
About five billion years from now, the core of the Sun will shrink and become hotter. The surface temperature will fall. The higher temperature of the center will increase the rate of thermonuclear reactions. The outer regions of the Sun will expand approximately 35 million miles, about the distance to Mercury, which is the closest planet to the Sun. The Sun will then be a red giant star. Temperatures on the Earth will become too high for life to exist.
Once the Sun has used up its thermonuclear energy as a red giant, it will begin to shrink. After it shrinks to the size of the Earth, it will become a white dwarf star. The Sun may throw off huge amounts of gases in violent eruptions called nova explosions as it changes from a red giant to a white dwarf.
After billions of years as a white dwarf, the Sun will have used up all its fuel and will have lost its heat. Such a star is called a black dwarf. After the Sun has become a black dwarf, the Earth will be dark and cold. If any atmosphere remains there, it will have frozen over the Earth’s surface.

When the Sun has used up its energy as a red giant, it will ....................

Choose the best answer

Nearly 200 of the 1500 native plant species in Hawaii are at risk of going extinct in the near future because they have been (1) ____ to such low numbers. Approximately 90 percent of Hawaii's plants are found nowhere else in the world but they are (2) ____ by alien invasive species such as feral goats, pigs, rodents and non- (3) ____ plants. The Hawaii Rare Plant Restoration Group is striving to (4) ____ the extinction of the 182 rare Hawaiian plants with fewer than 50 individuals remaining in the (5) ____. Since 1990, (6) ____ a result of their “Plant Extinction Prevention Program‟, sixteen species have been brought into (7) ____ and three species have been reintroduced. Invasive weeds have been removed in key areas and fencing put up in order to (8) ____ plants in the wild.

In the future the Hawaii Rare Plant Restoration Program aims (9) ____ collecting genetic material from the remaining plants in the wild for storage as a safety net for the future. They also aim to manage wild populations and where possible reintroduce species into (10) ____.

(9) ____

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: 
We are descendents of the ice age. Periods of glaciation have spanned the whole of human existence for the past 2 million years. The rapid melting of the continental glaciers at the end of the last ice age spurred one of the most dramatic climate changes in the history of the planet. During this interglacial time, people were caught up in a cataclysm of human accomplishment, including the development of agriculture and animal husbandry. Over the past few thousand years, the Earth’s climate has been extraordinarily beneficial, and humans have prospered exceedingly well under a benign atmosphere. Ice ages have dramatically affected life on Earth almost from the very beginning. It is even possible that life itself significantly changed the climate. All living organisms pull carbon dioxide out of the atmosphere and eventually store it in sedimentary rocks within the Earth’s crust. If too much carbon dioxide is lost, too much heat escapes out into the atmosphere. This can cause the Earth to cool enough for glacial ice to spread across the land. In general the reduction of the level of carbon dioxide in the atmosphere has been equalized by the input of carbon dioxide from such events as volcanic eruptions. Man, however, is upsetting the equation by burning fossil fuels and destroying tropical rain forests, both of which release stored carbon dioxide. This energizes the greenhouse effect and causes the Earth to warm. If the warming is significant enough, the polar ice caps eventually melt. The polar ice caps drive the atmospheric and oceanic circulation systems. Should the ice caps melt, warm tropical waters could circle the globe and make this a very warm, inhospitable planet. Over the past century, the global sea level has apparently risen upwards of 6 inches, mainly because of the melting of glacial ice. If present warming trends continue, the seas could rise as much as 6 feet by the next century. This could flood coastal cities and fertile river deltas, where half the human population lives. Delicate wetlands, where many marine species breed, also would be reclaimed by the sea. In addition, more frequent and severe storms would batter coastal areas, adding to the disaster of the higher seas. The continued melting of the great ice sheets in polar regions could cause massive amounts of ice to crash into the ocean. This would further raise the sea level and release more ice, which could more than double the area of sea ice and increase correspondingly the amount of sunlight reflected back into space. The cycle would then be complete as this could cause global temperatures to drop enough to initiate another ice age.

According to the passage, carbon dioxide is stored in each of the following EXCEPT

Probably the most famous film commenting on the twentieth-century technology is Modem Times, made in 1936. Charlie Chaplin was motivated to make the film by a reporter who, while interviewing him, happened to describe the working conditions in industrial Detroit. Chaplin was told that healthy young farm boys were lured to the city to work on automotive assembly lines. Within four or five years, these young men's health was destroyed by the stress of work in the factories.
The film opens with a shot of a mass of sheep making their way down a crowded ramp. Abruptly, the film shifts to a scene of factory workers jostling one another on their way to a factory. However, the rather bitter note of criticism in the implied comparison is not sustained. It is replaced by a gentle note of satire. Chaplin prefers to entertain rather than lecture.
Scenes of factory interiors account for only about one-third of Modern Times, but they contain some of the most pointed social commentary as well as the most comic situations. No one who has seen the film can ever forget Chaplin vainly trying to keep pace with the fast-moving conveyor belt, almost losing his mind in the process. Another popular scene involves an automatic feeding machine brought to the assembly line so that workers need not interrupt their labor to eat. The feeding machine malfunctions, hurling food at Chaplin, who is strapped in his position on the assembly line and cannot escape. This serves to illustrate people's utter helplessness in the face of machines that are meant to serve their basic needs.
Clearly, Modern Times has its faults, but it remains the best film treating technology within  a social context. It does not offer a radical social message, but it does accurately reflect the sentiment of many who feel they are victims of an over - mechanized world

The author refers to all of the following notions to describe Modern Times EXCEPT  “     ”.

Choose the letter A, B, C or D to answer these following questions:
Alligators have always been the most dangerous predators of the Florida Everglades, but their long-held position is now being challenged by a growing population of Burmese pythons.
The Burmese python, a giant snake measuring up to 20 feet long and weighing up to 200 pounds, is very popular among exotic pet owners. However, as the dead snakes grow, they become more difficult to cage and handle. To avoid dealing with the snakes, the owners irresponsibly release them into the wild. Since the Everglades is quietly similar to the python's native environment of Southeast Asia, they survive and prosper without difficulty.
The issue with the Burmese pythons is their choice of meals. They eat alligators and endangered birds, which creates strain on an already fragile ecosystem. Recently a 13-foot long Burmese python was found with a 5-foot alligator bursting from its stomach. The python died tried to eat the alligator but a larger one would have easily won the struggle. With over 30,000 Burmese pythons now living over the Everglades, a solution to stop this invasive species is necessary. If the pythons are left unchecked, there is a strong possibility they will wipe out a variety of species needed for the functioning of the Everglades ecosystem.

What happens if human don’t control the population of pythons?

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.
Engineers have dreaming of an underwater link between Britain and France (35)_____1802. Finally in 1994 the Channel Tunnel ( nicknamed "The Chunnel" by the English) was (36)______ opened.
This fifteen billion dollar project took seven years to (37)_____. It is about 50 km long and built 45metres under the seabed .The trains which go through the Chunnel can travel at up 300 km/h due to the (38)_______electrical system.
The journey from London to Paris via the Chunnel takes just three hours. It is also (39)______ for drivers since they can load their cars onto the trains. They don't need to book in (40)______ , as trains (41)_______every few minutes. However, while on the train, there isn't much to do and many (42)_________ the Chunnel for this (43)________ the ferries , there is no duty-free shopping , no videogame parlou or refreshment stand (44)________can you look outside and enjoy the view . As a result, many would find the Chunnel unappealing and would take the ferry instead.
(40).......................................... 

Read the passage and answer the questions.

During my last couple of years as a student here at Union High, I have noticed that there is nothing to do during our occasional free periods. Hanging around in the hallways or in the library with friends isn't productive or relaxing. The student body council noticed this as well and brought it to the attention of Mr. Swanson and the rest of the faculty. A meeting to discuss the issue occurred last Friday, February 10th, in the all - school meeting room.

The faculty not only agreed that there wasn't much to do during these free periods, but also seemed determined to find a solution. The student body council and the faculty talked about different ideas for a long time. The faculty had noticed that some students don't like using their free periods for studying. Instead, they spend their time disrupting the students who want to study by being noisy in the library. By the end of the meeting, the faculty had decided to put a pool table and a ping pong table in our student lobby at the start of next semester.

I know some people will be concerned about getting their work done with these potential distractions, but I believe this will help us all in enjoying our time at school. I agree that it's important to complete our work but it is just as important to enjoy ourselves and to relax with our friends. School is already such a stressful place. It makes many students feel worried and anxious. We want our school to be a friendly place so that students want to come every day. Students should remember that this change will make the library a lot quieter. Because of this, the students who want to study will be able to do so in peace.

To all the students at Union High, I sincerely hope that you enjoy the new additions to our lobby. Hopefully, they will make our free periods a lot more relaxing. If you happen to have one of the same free periods as I do, then please challenge me to a game of pool!

According to the author, new facilities ____.

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:
    Animation traditionally is done by hand-drawing or painting successive frame of an object, each slightly different than the proceeding frame. In computer animation, although the computer may be the one to draw the different frames, in most cases the artist will draw the beginning and ending frames and the computer will produce the drawings between the first and the last drawing. This is generally referred to as computer-assisted animation, because the computer is more of a helper than an originator. 
    In full computer animation, complex mathematical formulas are used to produce the final sequences of pictures. These formulas operate on extensive databases of numbers that defines the objects in the pictures as they exist in mathematical space. The database consists of endpoints, and color and intensity information. Highly trained professionals are needed to produce such effects because animation that obtains high degrees of realism involves computer techniques from three-dimensional transformation, shading, and curvatures.
    High-tech computer animation for film involves very expensive computer systems along with special color terminals or frame buffers. The frame buffer is nothing more than a giant image memory for viewing a single frame. It temporarily holds the image for display on the screen.
    A camera can be used to film directly from the computer’s display screen, but for the highest quality images possible, expensive film recorders are used. The computer computers the positions and colors for the figures in the picture, and sends this information to the recorder, which captures it on film. Sometimes, however, the images are stored on a large magnetic disk before being sent to the recorder. Once this process is completed, it is replaced for the next frame. When the entire sequence has been recorded on the film, the film must be developed before the animation can be viewed. If the entire sequence does not seem right, the motions must be corrected, recomputed, redisplayed, and rerecorded. This approach can be very expensive and time – consuming. Often, computer-animation companies first do motion tests with simple computer-generated line drawings before selling their computers to the task of calculating the high-resolution, realistic-looking images.

The word “Once” in the fourth paragraph is closest in meaning to ______.

Choose the best answer:
After more than fifty years of television, it might seem only obvious to conclude that it is here to (1) ______ . There have been many objections to it during this time, of course, and (2) ______ a variety of grounds. Did it cause eye-strain? Was the (3) ______ bombarding us with radioactivity? Did the advertisements contain subliminal messages, persuading us to buy more? Did children turn to violence through watching it, either because so (4) ______ programmes taught them how to shoot, rob, and kill, or because they had to do something to counteract the hours they had spent glued to the tiny screen? Or did it simply create a vast passive (5) ______ drugged by glamorous serials and inane situation (6) ______ ? On the other hand did it increase anxiety by sensationalizing the news [or the news which was (7) ______ by suitable pictures] and filling our living rooms with war, famine and political unrest? (8) ______ in all, television proved to be the all-purpose scapegoat for the second half of the century, blamed for everything, but above all, eagerly watched. For no (9) ______ how much we despised it, feared it, were bored by it, or felt that it took us away from the old paradise of family conversation and hobbies such as collecting stamps, we never turned it off. We kept staring at the screen, aware that our own tiny (10) ______ was in if we looked carefully.
10. 

Read the passage below and decide whether the statements are TRUE or FALSE?

   According to the Academic Ranking of World Universities, more than 30 of the highest-ranked 45 institutions are in the United States, as measured by awards and research output. Public universities, private universities, liberal arts colleges, and community colleges all have a significant role in higher education in the United States. An even stronger pattern is shown by the Webometrics Ranking of World Universities with 103 US universities in the World's Top 200 universities.

   The 2006 American Community Survey conducted by the United States Census Bureau found that 19.5 percent of the population had attended college but had no degree, 7.4 percent held an associate's degree, 17.1 percent held a bachelor's degree, and 9.9 percent held a graduate or professional degree.

   Educational attainment in the United States is similar to that of other developed countries. Colleges and universities in the U.S. vary in terms of goals: some may emphasize a vocational, business, engineering, or technical curriculum while others may emphasize a liberal arts curriculum. Many combine some or all of the above. Students can apply to some colleges using the Common Application. There is no limit to the number of colleges or universities to which a student may apply, though an application must be submitted for each.'

20 percent of the population had attended college but had no degree

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THE THREAT TO THE ENVIRONMENT

Nowadays people are more aware that wildlife all over the world is in danger. Many (1)________of animals are threatened, and could easily become (2)______ if we do not make an effort to protect them. There are many (3)_______ for this. In some cases, animals are hunted for their fur or for othervaluable parts of their bodies. Some birds, such as parrots, are caught (4)________and sold as pets. For many animals and birds, the problem is that their habitat - the (5)________where they live - is disappearing. More (6)________is used for farms, for houses or industry, and there are fewer open (7)________than there once were. Farmers use powerful chemicals to help them grow better (8)________, but these chemicals pollute the environment and (9)________wildlife. The most successful animals on earth - human beings - will soon be the only Ones left, unless we can (10)________this problem.

(1)________

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

"Nowadays people are more aware that wildlife all over the world is in (1)….  . Many species of animals are threatened, and could easily become (2)….   if we do not make an effort to (3)….. them. There are many reasons for this. In some cases, animals are (4)….. for their fur or for other valuable parts of their bodies. Some birds, such as parrots, are caught (5)…. , and sold as pets. For many animals and birds, the problem is that their habitats - the place where they live - is (6)…. . More (7)….  is used for farms, for houses and industry, and there are fewer open spaces than there once were. Farmers use powerful Chemicals to help them grow better (8)…. , but these Chemicals pollute the environment and (9)… wildlife. The most successful animals on Earth, human beings, will soon be the only ones (10)….. unless we can solve this problem."

9. but these Chemicals pollute the environment and (9)… wildlife. 

It's often said that we learn things at the wrong time. University students frequently do the minimum of work because they're crazy about a good social life instead. Children often scream before their piano practice because it’s so boring. They have to be given gold stars and medals to be persuaded to swim, or have to be bribed to take exams. But the story is different when you’re older.
Over the years, I've done my share of adult learning. At 30, I went to a college and did courses in History and English. It was an amazing experience. For starters, I was paying, so there was no reason to be late - I was the one frowning and drumming my fingers if the tutor was late, not the other way round. Indeed, if I could persuade him to linger for an extra five minutes, it was a bonus, not a nuisance. I wasn't frightened to ask questions, and homework was a pleasure not a pain. When I passed an exam, I had passed it for me and me alone, not for my parents or my teachers. The satisfaction I got was entirely personal
Some people fear going back to school because they worry that their brains have got rusty. But the joy is that, although some parts have rusted up, your brain has learnt all kinds of other things since you were young. It has learnt to think independently and flexibly and is much better at relating one thing to another. What you lose in the rusty department, you gain in the maturity department.
In some ways, age is a positive plus. For instance, when you're older, you get less frustrated. Experience has told you that, if you're calm and simply do something carefully again and again, eventually you'll get the hang of it. The confidence you have in other areas - from being able to drive a car, perhaps - means that if you can’t, say, build a chair instantly, you don't, like a child, want to destroy your first pathetic attempts. Maturity tells you that you will, with application, eventually get there.
I hated piano lessons at school, but I was good at music. And coming back to it, with a teacher who could explain why certain exercises were useful and with musical concepts that, at the age of ten, I could never grasp, was magical. Initially, I did feel a bit strange, thumping out a piece that I'd played for my school exams, with just as little comprehension of what the composer intended as I'd had all those years before. But soon, complex emotions that I never knew poured out from my fingers, and suddenly I could understand why practice makes perfect.

What is the writer's main purpose in the passage?

The Sun today is a yellow dwarf star. It is fueled by thermonuclear reactions near its center that convert hydrogen to helium. The Sun has existed in its present state for about four billion six hundred million years and is thousands of times larger than the Earth.
By studying other stars, astronomers can predict what the rest of the Sun's life will be like.
About five billion years from now, the core of the Sun will shrink and become hotter. The surface temperature will fall. The higher temperature of the center will increase the rate of thermonuclear reactions. The outer regions of the Sun will expand approximately 35 million miles, about the distance to Mercury, which is the closest planet to the Sun. The Sun will then be a red giant star. Temperatures on the Earth will become too high for life to exist.
Once the Sun has used up its thermonuclear energy as a red giant, it will begin to shrink. After it shrinks to the size of the Earth, it will become a white dwarf star. The Sun may throw off huge amounts of gases in violent eruptions called nova explosions as it changes from a red giant to a white dwarf.
After billions of years as a white dwarf, the Sun will have used up all its fuel and will have lost its heat. Such a star is called a black dwarf. After the Sun has become a black dwarf, the Earth will be dark and cold. If any atmosphere remains there, it will have frozen over the Earth’s surface.

This passage is intended to ..................