Read the following passage and choose the best answer (A, B, C, D):
Advances in technology have generated revolutionary applications that could change the face of education as we know it today. Online learning, also known as electronic learning, may (33)......the future of education thanks to recent developments in the Internet and multimedia technologies.It is anticipated that cyberspace institutions or online universities will replace traditional educational (34) .......Virtual classrooms will be multi-functional, acting simultaneously as learning platforms, forums and (35).......networks. They will be geared towards promoting the acquisition of knowledge as a life- long endeavour, (36)........occurs through global collaboration. Cyberspace institutions can go a long way towards achieving this as they are able to liberate us from the limitations of time and space. Flexibility of time and location makes e-learning a highly accessible, international resource. (37) .........., prospective students will, regardless of age, background or origin, have unlimited access to both formal and informal learning opportunities. The pursuit of knowledge will consequently become an end in itself and not a means to an end

Read the following passage and choose the best answer (A, B, C, D):
The history of American newspapers begins in the early 18th century with the publication of the first colonial newspapers. American newspapers began as modest affairs-a sideline for printers. They became a political force in the campaign for American independence. After independence, the first article of U.S. Constitution guaranteed freedom of the press. The U.S. Postal Service Act of 1792 provided substantial subsidies: Newspapers were delivered up to 100 miles for a penny and beyond for 1.5 cents, when first class postage ranged from six cents to a quarter. The American press grew rapidly during the First Party System (1790s-1810s) when both parties sponsored papers to reach their loyal partisans. From the 1830s onward, the Penny press began to play a major role in American journalism and its interests seemed to remarkably surprised the management board in the journal industry. Technological advancements such as the telegraph and faster printing presses in the 1840s also helped to expand the press of the nation as it experienced rapid economic and demographic growth. Editors typically became the local party spokesman, and hard-hitting editorials were widely reprinted. By 1900 major newspapers had become profitable powerhouses of advocacy, muckraking and sensationalism, along with serious, and objective news-gathering. During the early 20th century, prior to rise of television, the average American read several newspapers per-day. Starting in the 1920s, changes in technology again morphed the nature of American journalism as radio and later, television, began to play increasingly important competitive roles. In the late 20th century, much of American journalism became housed in big media chains. With the coming of digital journalism in the 21st century, all newspapers faced a business crisis as readers turned to the Internet for sources and advertisers followed them  
1. What is the main idea of the passage?

Read the following passage and choose the best answer (A, B, C, D):
Elephants need a large amount of habitat because they eat so much. Humans have become their direct competitors for living space. Human populations in Africa and Asia have quadrupled since the turn of the century, the fastest growth rate on the planet. Forest and savanna habitat has been converted to cropland, pastureland for livestock, and timber for housing and fuel. Humans do not regard elephants as good neighbors. When humans and elephants live close together, elephants raid crops, and rogue elephants rampage through villages. Local people shoot elephants because they fear them and regard them as pests. Some countries have established culling programs: park officials or hunters kill a predetermined number of elephants to keep herds manageable and minimize human-elephant conflicts. Hunting has been a major cause of the decline in elephant populations. Elephants became prized trophies for big-game hunters after Europeans arrived in Africa. More recently, and more devastatingly, hunters have slaughtered elephants for their ivory tusks. The ivory trade became a serious threat to elephants in the 1970s. A sudden oil shortage caused the world economy to collapse, and ivory became more valuable than gold. In fact, ivory has been called “white gold” because it is beautiful, easily carved, durable, and pleasing to the touch. Most of the world’s ivory is carved in Japan, Hong Kong, and other Asian countries, where skilled carvers depend on a supply of ivory for their livelihoods  Hunting elephants is no longer legal in many African countries, but poaching was widespread until very recently. For many the high price of ivory, about $100 a pound in the 1980s, was too tempting to resist. Local people often had few other ways to make a living, and subsistence farmers or herders could make more by selling the tusks of one elephant than they could make in a dozen years of farming or herding. As the price of ivory soared, poachers became more organized, using automatic weapons, motorized vehicles, and airplanes to chase and kill thousands of elephants. To governments and revolutionaries mired in civil wars and strapped for cash, poaching ivory became a way to pay for more firearms and supplies. Poaching has caused the collapse of elephants’ social structure as well as decimating their numbers. Poachers target the biggest elephants because their tusks are larger. They often kill all the adults in the group, leaving young elephants without any adults to teach them migration routes, dry-season water sources, and other learned behavior. Many of Africa’s remaining elephant groups are leaderless subadults and juveniles.
2. What does the word “them” in the second paragraph refer to?

Read the following passage and choose the best answer (A, B, C, D):
Many AI researchers roll their eyes when seeing this headline: “Stephen Hawking warns that rise of robots may be disastrous for mankind.” And as many have lost count of how many similar articles they’ve seen. Typically, these articles suggest we should worry about robots rising up and killing us because they’ve become conscious and/or evil. On a lighter note, such articles are actually rather impressive, because they succinctly summarize the scenario that AI researchers don’t worry about. That scenario combines as many as three separate misconceptions: concern about consciousness, evil, and robots. If you drive down the road, you have a subjective experience of colors, sounds, etc. But does a self-driving car have a subjective experience? Does it feel like anything at all to be a self-driving car? Although this mystery of consciousness is interesting in its own right, it’s irrelevant to AI risk. If you get struck by a driverless car, it makes no difference to you whether it subjectively feels conscious. In the same way, what will affect us humans is what superintelligent AI does, not how it subjectively feels. The fear of machines turning evil is another red herring. The real worry isn’t malevolence, but competence. A superintelligent AI is by definition very good at attaining its goals, whatever they may be, so we need to ensure that its goals are aligned with ours. Humans don’t generally hate ants, but we’re more intelligent than they are – so if we want to build a hydroelectric dam and there’s an anthill there, too bad for the ants. The beneficial-AI movement wants to avoid placing humanity in the position of those ants In fact, the main concern of the beneficial-AI movement isn’t with robots but with intelligence itself: specifically, intelligence whose goals are misaligned with ours. To cause us trouble, such misaligned superhuman intelligence needs no robotic body, merely an internet connection – this may enable outsmarting financial markets, out-inventing human researchers, out-manipulating human leaders, and developing weapons we cannot even understand. Even if building robots were physically impossible, a super-intelligent and superwealthy AI could easily pay or manipulate many humans to unwittingly do its bidding. The robot misconception is related to the myth that machines can’t control humans. Intelligence enables control: humans control tigers not because we are stronger, but because we are smarter.  
4. The word “subjective” in paragraph 2 is closest in meaning to _______

Rewrite the sentence:
Henry tasted the pleasures of modern city life. Then he found life in his village hard and unattractive.

Read the following passage and choose the best answer (A, B, C, D):
The knock–on effect of volunteering on the lives of individuals can be profound. Voluntary work helps foster independence and imparts the ability to deal with different situations, often simultaneously, thus teaching people how to (1) _______ their way through different systems. It therefore brings people into touch with the real world, and hence, equips them for the future. Initially, young adults in their late teens might not seem to have the expertise or knowledge to impart to athare that attencher or an ariculturalist or a nurse would have, (2) ________ they do have many skills can help others. And in the absence of any particular talent, their energy and enthusiasm can be harmes the benefit (3) _______ their fellow human beings, and ultimately themselves. From all this, the gain to any community no matter how many volunteers are involved is (4)_______ . Employers will generally look favorably on people (5) _______have shown an ability to work as part of team. It demonstrates a willingness to learn and an independent spirit, which would be desirable qualities in any employee.

Choose the best answer:
Don't forget _____ your identity card with you to the interview.

Read the following passage and choose the best answer (A, B, C, D):
When people marry, they’re usually in love and happy to be tying the (1) ____. But after that, things tend to change. (2) __________ average, couples’ satisfaction with their marriage declines during the first years of marriage and, if the decline is particularly steep, divorce may follow. The course of true love runs downhill. For around 30 years, researchers have studied how having children affects a marriage, and the results are (3) ______: the relationship between spouses suffers once kids come along. Comparing couples with and (4) ______ children, researchers found that the rate of the decline in relationship satisfaction is nearly twice as steep for couples who have children than for childless couples. In the (5) ______ that a pregnancy is unplanned, the parents experience even greater negative impacts on their relationship. The irony is that even as the marital satisfaction of new parents declines, the likelihood of them divorcing also declines. So, having children may make you miserable, but you’ll be miserable together

Read the following passage and choose the best answer (A, B, C, D):
Graphic novels, as the name suggests, are books written and illustrated in the style of a comic book. Adults may feel that graphic novels do not help children become good readers. They believe that this  type of  reading material  somehow prevents  "real"   reading. (1)_____ , many quality graphic novels are now being seen as a method of storytelling on the same level as novels, films or audiobooks. Many librarians and teachers are now accepting graphic novels as proper literature for children as they (2)____ young people and motivate them to read. This has been especially true with children who are not (3)_________to read, especially boys.Language learners are also motivated by graphic novels because the pictures provide clues to the meaning of the words. Therefore, they will (4)______ new vocabulary more quickly. Many teachers have reported great success when they used graphic novels with their students, especially in the areas of English, social studies and art. The idea that graphic novels are too simple to be regarded as serious reading is no longer valid. Reading them can, undoubtedly, help students develop the skills (5) _____ are necessary to read more challenging works

Choose the best answer:
He’s so brilliant and he can do anything - ……….

Read the following passage and choose the best answer (A, B, C, D):
Books have been around for thousands of years. When ancient civilizations first started developing writing systems, they would write on just about anything, from stone to tree bark. Ancient Egyptians were the first to use paper-like materials, called “papyrus”, which they made by pounding flat the woven stems of the papyrus plant. It was not long before the ancient Egyptians began gluing together papyrus sheets to form scrolls, which were the first steps toward books as you know. The birthplace of bookbinding is considered to be India in the 2nd century B.C., where Hindi scribes would bind palm leaves that were etched with religious texts between two wooden boards using twine. The technique became popular in the Middle East and Eastern Asia, and spread to the Romans by the 2nd century A.D. In the mid-15th century, German Johannes Gutenberg invented the first mechanical printing press. His invention was revolutionary because it enabled mass production of booksfor the first time. Before the printing press, a few pages per day could be produced by handcopying. Afterward, printing presses could produce as many as 3,600 pages per day. Today, modern publishers take advantage of incredible advances in technology to produce books in many sizes and shapes very quickly. Although there are many types of processes and machines available, most processes involve similar steps. Printers print the text of a book on large sheets of paper, sometimes as large as a newspaper page. Working with large volumes of paper allows printers to lower costs and produce books more efficiently.The large sheets are then cut into smaller pages that are still about twice the size of a finished book. The smaller pages are then divided into small groups, folded in half, and sewn together. Lastly, the folded and sewn pages are cut down to their finished size and glued to the spine of the final book’s cover. Depending on the quality of the book, additional finishing touches may be added, such as blank pages at the front and back of the book or special tape around the edges of the cover to increase durability. Although printed books may never go away completely, today’s readers will most certainly soon become more familiar with e-books. “E-book” refers to an electronic book, which is simply the text of a book displayed electronically, either via the Internet, a CD-ROM, a tablet, an e-book reader, or even a mobile phone. As electronic devices, such as tablets and mobile phones, become more commonplace, e-books are expected to become more and more popular. One of the benefits of e-books is that they save paper, which helps the environment by reducing the demand for trees  
8. Which of the following is TRUE according to the passage?

Read the following passage and choose the best answer (A, B, C, D):
Hamams, or bath houses, are a traditional part of Turkish culture. They represent an important piece of Turkey’s long history and serve as a window into the past. However, these bath houses are quickly disappearing because of the changing habits of the Turkish people. Hamams hold a strong place in the history of Turkey and many date back hundreds of years. Traditionally, all kinds of people went to hamams because Islam has strict laws for cleanliness. Believers must wash themselves regularly, particularly before their daily prayers. As most people in Turkey didn’t have access to running water in their homes, the hamam was the perfect to get clean, relax, and catch up with friends. Today, however, the tradition of going to the humam is quickly dying out for many young people. Now almost everyone has running water in their bathrooms, so they prefer to bathe at home. As a result, Turkish people are not going to humans as often as they used to. These days, instead of relying on locals, many hamams are trying to attract foreign tourists. Some of the best hamams in Turkey are located in Istanbul, the country’s largest city. The Cagaloglu hamam is a great example. It was a gift to the people from the Sultan in 1741 and is one of the last old hamams to be built during the Ottoman Empire. Many visitors are impressed by the high domed ceilings, marble floors, and marble walls used throughout. A typical session at a hamam can last well over an hour. Visitors will be welcomed into camekan, or entrance hall. There they will be able to relax with friends and chat over a cup of tea. They will also be able to change into the customary pestemal, or Turkish towel, which wraps around the waist like a skirt. When ready, visitors will head into the hararet, or hot room. There they will lie on the hot floor and be scrubbed clean and massaged by one of the in-house masseurs or masseuses. Men and women always bathe separately, but their experience are very similar. Although many hamams are in danger of closing, they will always remain a part of Turkish culture. An experience in one of Istanbul’s famous bath houses is not to be misses on any visit to Turkey. It will certainly leave you refreshed, relaxed, and squeaky clean for your next adventure
8. Which of the following is NOT true about hamams?

Read the following passage and choose the best answer (A, B, C, D):
“What we’re seeing in Australia, in a completely different environment, are fires that are approaching or even exceeding the magnitude of things that we only saw in the most remote forested regions in the world,” said Ross Bradstock, the director of the Center for Environmental Risk Management of Bushfires at the University of Wollongong in New South Wales. The numbers from Australia dwarf those from some of the most high-profile fires in recent years. The bushfires in southeastern Australia this season have burned about eight times as much land as the 2018 fires in California, which covered nearly two million acres and were the worst in that state’s recorded history.  In Australia’s history, most bad fire seasons have coincided with the warming of an El Niño pattern. But that is not the case this time, showing how much this season stands out and the danger the country faces with more unpredictable weather patterns in the future. “While scientists have long predicted that climate change would bring longer and more intense fire seasons”, Dr. Bradstock said, “Under his projections, Australia would not have seen this kind of devastation for another 40 to 50 years”.  “I guess I’m as shocked as anyone about what’s unfolding and, probably, like everyone else who’s involved and affected, we’ll very quickly recalibrate thinking about what we’re doing,” he said. Recalibrating means expecting these phenomenal fires to continue to occur, particularly as Australia’s drought shows few signs of ending and temperatures are expected to continue to climb after the warmest decade on record.  “We would be extremely foolish, given all the evidence and the magnitude of this event, to just laugh it off as a one-off phenomenon,” Dr. Bradstock said. “I think we have to get ready to deal with a season like this again in the not-too-distant future.” 
5. The word “it” in paragraph 4 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:
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.

In line 3, the words pays heed to are closest in meaning to ………………...

Read the following passage and choose the best answer (A, B, C, D):
Bagpipe music played, wreaths were sent and Amazing Grace was sung. A  black shroud was laid upon a makeshift urn. It was a funeral, of course, for which such displays of respect are common. But in this case, the people living in a small Nova Scotia community had gathered to pay their respects not to a person who had died, but to a post office.  The grief might have been hard for outsiders to understand, but not for those living in Head of St. Margaret’s Bay, N.S., where the post office run by Verna Dunlop was a big part of their small, tight-knit community. The post office, which had been located in the back of Dunlop’s home, was not just a utilitarian service kiosk where residents had to go to pick up their mail. According to locals, it was also a community hub where people gathered to catch up on the town gossip, or to enjoy a cup of the coffee the postmaster had been brewing for them. “It’s really the centre of the village,” said one woman, explaining what the post office meant to the people living there.  There had been a post office located in Head of St. Margaret’s Bay since before Confederation. And local residents spent months fighting to keep the one they had. But Canada Post made the decision to close it, as it was losing money. It was replacing the post office with sets of newly installed super mailboxes.  Many people in town weren’t convinced the coming changes were for the better. “We do not want those super mailboxes. We want to have a community life,” he said. At the mock funeral, Dunlop choked up as she said she hoped “this is going to stop,” alluding to the fact that it wasn’t just Head of St. Margaret’s Bay that was losing its post office. “We hope that the way of life that we’re used to we can keep,” she added. Canada Post had closed 40 such rural post offices that year and had long-term plans to close more than 5,000 of them across the country. “Just as Verna Dunlop’s post office came to symbolize for these people the best qualities of rural life, so does its passing remind them of the steady erosion of that way of life,” said Evans.
5. The word “they” in paragraph 3 refers to _____

Read the following passage and choose the best answer (A, B, C, D):
The Internet is very much like television, in which it takes time away from other pursuits, provides entertainment and information, but in no way can compare with the warm, personal experience of reading a good book. This is not the only reason why the Internet will never replace books, for books provide the in-depth knowledge of a subject that sitting in front of a computer monitor cannot provide. We can download text from an Internet source, but the aesthetic quality of sheets of downloaded text leave much to be desired. A welldesigned book enhances the reading experience. The book is still the most compact and inexpensive means of conveying a dense amount of knowledge in a convenient package. The easy portability of the book is what makes it the most user-friendly format for knowledge ever invented. The idea that one can carry in one’s pocket a play by Shakespeare, a novel by Charles Dickens or Tom Clancy, Plato’s Dialogues, or the Bible in a small paperback edition is mind-boggling. We take such uncommon convenience for granted, not realizing that the book itself has undergone quite an evolution since the production of the Gutenberg Bible in 1455 and Shakespeare’s First Folio in 1623, just three years after the Pilgrims landed at Plymouth to colonize the New World. Not only has the art and craft of printing and book manufacturing been greatly improved over the centuries, but the great variety of subject matter now available in books is astounding, to say the least. In fact, the Internet requires the constant input of authors and their books to provide it with the information that makes it a useful tool for exploration and learning.  Another important reason why the Internet will never replace books is because those who wish to become writers want to see their works permanently published as books - something you can hold, see, feel, skim through, and read at one’s leisure without the need for an electric current apart from a lamp. The writer may use a word processor instead of a typewriter or a pen and pad, but the finished product must eventually end up as a book if it is to have value to the reading public. The writer may use the Internet in the course of researching a subject just as he may use a library for that purpose, but the end product will still be a book.
2. What does the word “this” in the first paragraph refer to?

Read the following passage and choose the best answer (A, B, C, D):
If you see someone who’s looking blue, just reach out and offer a kind word, a smile, a hug. Sometimes people just feel (1) ____ they need someone to care. Maybe they’re confused and not sure what’s going on just in the moment, or in a bigger picture such as where their lives are (2) ____. The purpose of our lives is to love, laugh, be happy and to grow together, sharing with one another. If we are all too busy (3) ____ someone who is in emotional need, it can leave the person wondering what’s the real point of everything. By reaching out and smiling, showing compassion, listening, offering a (4) ____ of gentle advice, you remind both yourself and the (5) ____ what the bigger picture is, and bring a little burst of more light and happiness into the world. Enough of those bursts and lights contribute to the tipping point towards a more compassionate and joyful world

Read the following passage and choose the best answer (A, B, C, D):
Once restricted to space stations and satellites, photovoltaics are now gaining popularity and becoming an increasingly viable option. Every day, the sun releases an enormous amount of energy, far more than the entire population consumes. Being that the sun is a sustainable, renewable, and inexhaustible source for generating electricity, not using it seems almost counter-intuitive, especially considering the social and environmental impacts of other forms of energy generation. But the technology to create electricity from the sun is by no means simple and still has some limitations, the most significant being price. The process of turning the sun’s rays into electrical energy all starts in the so-called photovoltaic cell. These cells are produced with two chemically altered silicon layers of which one is missing elections and the other is electron-overloaded. When the photons from the sunlight reach the surface, these electrons gain the ability to move, generating a flow that creates an electric current. Each cell generates a small amount of energy and a panel is usually made of between 36 and 72 photovoltaic cells. By connecting several panels together, a photovoltaic system is created. Eight to ten panels is enough to power a small house. Evidently, however, this statistic is influenced by some factors, such as the efficiency of the panels, the amount of sunshine in the region, and the energy demand of the residence itself.  Importantly, photovoltaic solar panels produce electricity in the form of direct current, meaning the electricity must pass through an inverter to transform it into alternating current - which is what is normally used in buildings, appliances, sockets, and light bulbs. Photovoltaic systems can facilitate energy generation in remote locations where infrastructural networks do not reach. In these cases, the system uses batteries to store electricity when less energy is used than is consumed, such as at night or on very cloudy days. However, it is also possible to use photovoltaics in systems connected to the power grid. In these cases, the excess energy goes to the electricity grid, creating energy “credits” for the building in question. In some countries, it is even possible to sell surplus energy, making the building a power plant for neighbors and method of paying off the investment more quickly.  
6. According to paragraph 2, what is incorrect about the photovoltaic system?

Read the following passage and choose the best answer (A, B, C, D):
Saving the planet is very much in vogue. It’s also in Harper’s Bazaar, Elle and Mademoiselle. It’s the message on fashion runways, in marketing strategies, in jewelry and accessory designs, on shopping bags and totes, in advertisements and on price tags. A naked fashion model wearing a hat of birch branches and lichen, as shown in Vogue this month, may not be everyone’s idea of environmental awareness. But the pervasiveness of ecological themes in the images and marketing of fashion is undeniable. It is also somewhat paradoxical. The fashion industry, whose driving philosophy involves encouraging consumers to discard the old and embrace the new, is now trying to push itself to the forefront of efforts to conserve and preserve. The environmental theme in fashion began as wispy touches and graphic exhortations in designer collections, not as some well-thought-out strategy of “green” marketing in which the environmental advantages of a product become part of the sales approach. Tendrils of ivy dangled from the ceiling at a Paris fashion show; a carpet of grass covered a runway in New York; models marched along in T-shirts or carrying signs all bearing slogans like “Clean Up or Die,” “Save the Sphere,” and “Environmental Protection Agents”.  The environmental spin on fashion has now moved into the mass market, where ‘’clothes with conscience’‘ make an extra tug at the buyer’s self-image. Bonjour, a jeans and sportswear company based in New York, has embarked on a program to ’‘change the individual’s outlook toward saving the environment’’ through educational tags. This summer, the first wave of what Bonjour executives said would be 50 million fashion items a year are to arrive in stores carrying tags with environmental tips from how to save water to how to reduce pollutants. Whether these tributes to nature will benefit the environment or even raise environmental awareness, with concomitant changes in individual behavior, is not clear. There is some skepticism. Professor Ewen says the new environmental symbolism should be viewed as part of an overall change in America’s economy, from one built on industrial production of hard goods to one based on “pure representation”. “Going back to fashion, the environment has become a commercial cliche separated from real concerns. What can be attached to this year’s fashion is merely the symbolism of environmental sanity.” 
8. Which of the following can be inferred from the passage?

Read the following passage and choose the best answer (A, B, C, D):
Sandwiches make a delicious snack any time. They are a common sight a picnics and  teas. Interestingly enough, the sandwich is (1) _______ invention of an 18th -century English Earl called John Montagu. Montagu was addicted to card games. He would play these games with his friends for long stretches of time. Often, he even found it too (2) _______ to stop his games for meals.  One day, in the middle of a game, Montagu was served a meal of sliced meat with bread. At the time, Montagu was playing the game that (3) _______ its players to cover cards one on top of another. As Montagu looked at both the game and his food, an idea came to his mind. “I can do the same with my food as well,” he thought. He took a slice of bread, placed a (4)______ of meat on it and covered that with another slice of bread. Montagu was very pleased with his invention because it allowed him to play cards with one hand and eat his meal with the other.  Montagu’s friends quickly (5) _______ to his idea and they named the new invention after him. As Montagu’s full title was “the Earl of Sandwich”, the new invention became known as a “sandwich”.

Read the following passage and choose the best answer (A, B, C, D):
Scientists have uncovered a new threat to the world’s endangered coral reefs. They  have found that most are incapable of growing quickly enough to compensate for rising sea levels triggered by global warming. The study suggests that reefs – which are already suffering serious degradation because the world’s seas are warming and becoming more acidic – could also become overwhelmed by rising oceans.  The research – led by scientists at Exeter University and published in Nature this week – involved studying growth rates for more than 200 tropical western Atlantic and Indian Ocean reefs. It was found only 9% of these reefs had the ability to keep up with even the most optimistic rates of sea-level rises forecast by the Intergovernmental Panel on Climate Change. “For many reefs across the Caribbean and Indian Ocean regions, where the study focused, rates of growth are slowing due to coral reef degradation,” said Professor Chris Perry, of Exeter University. “Meanwhile, rates of sea-level rise are increasing – and our results suggest reefs will be unable to keep up. As a result, water depths above most reefs will increase rapidly through this century.”  Sea levels rose by several inches over the past century and measurements indicate the speed of this increase is now rising significantly. Two key factors are involved: climate change is making ocean water warmer and so it expands. And as ice sheets and glaciers melt, they increase amounts of water in the oceans.  At the same time, reefs are being weakened by ocean warming and also by ocean acidification, triggered as the seas absorb more and more carbon dioxide. These effects lead to bleaching events that kill off vast stretches of coral and limits their ability to grow.  “Our predictions, even under the best case scenarios, suggest that by 2100, the inundation of reefs will expose coastal communities to significant threats of shoreline change,” said co-author Prof Peter Mumby of Queensland University. This point was backed by US marine scientist Ilsa Kuffner writing in a separate comment piece for Nature. “The implications of the study are dire. Many island nations and territories are set to quickly lose crucial natural resources.” 
5. What does the phrase “these effects” in paragraph 4 refer to?