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”.

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The term “generation gap” may have been coined not long ago but the problem itself is as old as the hills. All sorts of conflicts and misunderstanding between younger and older generations occur in probably every family. Adults complain about arrogance and insensitivity of young people whereas the latter claim that their parents have no idea about what they are going through. There seems to be no perfect solution to this problem as the young and the old find it difficult, if not impossible, to communicate and accept opposite views. The fact that teenagers develop different values from those held by their parents leads to numerous conflicts. There are many reasons why the problem of generation gap arises. First of all, the period of adolescence is difficult. Teenagers are not children any longer, but they are no adults yet. They search for a sense of identity and crave independence. On the other hand, they depend on their parents financially and still need their parent consent when they want to go out, go for holidays, buy something expensive, invite friends home, etc. Very often teenagers treat their parents like enemies especially when they are not permitted to do one thing or another. Obviously, it is understandable when parents insist a teenager returns home before midnight. They have a wide knowledge of the world and all kinds of risks involved – reckless youngsters see no danger in walking alone in the middle of the night or getting a lift from a stranger who might be a serial killer. When children grow up and start their own families they are able to admit that their parents were usually right, although a bit overprotective at times  However, we must remember that adolescence is the period of making important decisions. Sixteen or seventeen-year-olds want to choose their career path or at least develop their talents, which in turn will enable them to decide upon a job later on. Secondly, it is in their late teens when they form their lifelong friendships, go for their first dates, analyze what qualities they will look for in their future partners. Unfortunately, a lot of parents do not want to accept the fact that their child is growing up and has the sole right to choose who she or he wants to become in the future. Such mothers and fathers often have their own idea what their child’s life should be. To my mind, this kind of behavior is really harmful and it can result in a very serious family conflict. Every now and then we meet forty-year-old people who accuse their parents of making them study the subject they hated or marrying the person they never loved. The generation gap problem, which usually disappears a few years later, in such families turns into an emotional wound which might never heal and the feeling of a wasted life on both parts. To sum up, although conflicts between teenagers and their parents are unavoidable, they definitely do not have to lead to an open war. My advice to parents is to try and treat teenagers as their equal partners and to accept their ideas. Teenagers should respect their mothers and fathers more, and be always ready to discuss serious problems with them. All in all, who else loves them more than their parents do?  
5. The word “crave” in paragraph 2 can best be replaced by _____

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Learning shouldn’t end when you reach a certain point in your career; it should be something you continuously pursue across your lifetime. As you mature, your areas of interest may change. Perhaps your personal and career goals may morph into something altogether different than what you originally intended. In some cases, life happens and you might find it necessary to take a break from your career or your education. But for people with a strong desire for lifelong learning, this pause is only temporary. Even though you may have begun an educational program and needed to take a pause later, it’s never too late to go back and finish what you started. People in modern age have more options to gain the knowledge they want and need. From a higher education standpoint, universities and colleges are working hard to transform themselves in different ways. For example, there has been a transition from traditional Ph.D.-style doctorates to applied doctorates like the Doctorate in Strategic Intelligence or Doctorate in Global Security. These academic programs have their students work to address real-world problems of practice. In this manner, they take the education they receive in their classes and work to apply it within the fields in which they are currently employed or hope to work in. In addition, some universities now offer dual degree programs, such as the dual master’s degree in emergency and disaster management and homeland security. Some institutions are also starting to provide accelerated degrees to allow their students to rapidly advance from a B.A. to an M.A., saving those students time and money on their educational pursuits. However, lifelong learning doesn’t just encompass full degree programs. With employers focusing on skillset development, there is an increasing desire for short program offerings as well. “Short programming” includes sets of courses that lead to a specific credential or badge. For instance, ASIS International offers a series of certifications, related to security and global studies, which can be used to add value to your professional portfolio. Another relevant certification is the Certified Threat Manager (CTM) certification offered by the Association of Threat Assessment Professionals. Short programming involves learning tracks, competency-based micro-credentials or stackable credentials. In some cases, certificates are perceived to be more valuable as they signal that their owner has current knowledge of a particular area; however, this perception differs from field to field
1. Which best serves as the title for the passage?

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Human’s avarice for ivory has resulted in thousands of unfathomable elephant atrocities and senseless suffering that has pushed the species to the brink of extinction. In 2015, the U.S. and China announced they will work together to enact a near complete ban on the import and export of ivory. As an industry that has largely been driven by China and, if substantiated, these claims could be a ray of light for one of the most endangered animals in the kingdom. However, as the famous saying goes, “for every action, there is an equal and opposite reaction.” With the worldwide attention on elephant ivory, hippo teeth, which can grow up to three-feet-long, have become the next target. Since the United Nations Convention on International Trade in Endangered Species officially imposed a ban on ivory trading in 1990, about 30,000 pounds per year of hippo teeth have been exported from Africa. On a recent trip to Kenya, I had the unfortunate displeasure of meeting these facts face-to-face. On the banks of the Mara River, the infamous transient point of the great wildebeest migration, I met a Conservancy Ranger, a local Kenyan, named Ivan. He led me along a narrow path above the riverbed to view pods of hippos. They clumped together in the river, every few minutes lifting their heads above the waterline to welcome my arrival. Despite their label as one of the most dangerous animals in Africa, they were playful to watch. Their tiny ears and eyes would appear from the murky river and then, with a splash, they would disappear. The river is everything to the hippo, Ivan explained, it is their lifeline. The only real time they leave the river is during their nightly ritual of traveling to nearby plains to consume grasses. Contrary to their aggressiveness, they are vegetarians. As we neared the end of our trek, we reached the Mara Bridge, spanning the divide between Kenya and Tanzania. An undeniable stench filled the air. Our gaze fell to the water beneath the structure, and as if to mark the metaphorical significance of the passage, lay a poached hippo. It had been killed the previous night, probably as it grazed unsuspectingly under the cover of darkness. They had found spear punctures in its body, and its teeth were missing. It had somehow, in unthinkable pain, made its way back to the river, its home, to die.
7. Which of the following best describe author’s feeling about the hippo in the last paragraph?

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All the different plants and animals in a natural community are in a state of balance. This balance is achieved by the plants and animals interacting (1) _______ each other and with their non-living surroundings. An example of a natural community is a woodland, and a woodland is usually dominated by a particular species of plant, such as the oak tree in an oak wood. The oak tree in this example is therefore called the dominant species but there are also many other types of plants, from brambles, bushes, and small trees to mosses, lichens and algae (2) __________ on tree trunks and rocks. The plants of a community are the producers: they use carbon dioxide, oxygen, nitrogen to build up their tissues using energy in the form of sunlight. The plant tissues form food for the plant-eating animals (herbivores) (3) _______ are in turn eaten by flesh-eating animals (carnivores). Thus, plants produce the basic food supply for all the animals of a community. The animals themselves are the consumers, and are either herbivores or carnivores. Examples of herbivores in a woodland community are rabbits, deer, mice and snails, and insects such as aphids and caterpillars. The herbivores are sometimes eaten by the carnivores. Woodland carnivores are of all sizes, from insects such as beetles and lacewings to animals such as owls, shrews and foxes. Some carnivores feed on herbivores, some feed on the smaller carnivores, (4) _______ some feed on both: a tawny owl will eat beetles and shrews as well as voles and mice. These food relationships between the different members of the community are known as food chains or food (5) ______. All food chains start with plants. The links of the chain are formed by the herbivores that eat the plants and the carnivores that feed on the herbivores. There are more organisms at the base of the food chain than at the top; for example, there are many more green plants than carnivores in a community

Choose the best answer:
Nam: Do young people you know get enough exercise? - Lan: ____

Find synonym:
ASEAN organised different projects and activities to integrate its members

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We’ve just come back exhausted after a two-week holiday in France. We were really stupid. On the last day we drove non-stop from Marseille to Calais- we should have (34)_____ our journey in Lyon or Paris. As if that wasn’t enough, the sea was so rough in the English Channel that the (35) _____ took three hours instead of one and a half. Next year we’ve decided we’re going on a cheap (36) _____ holiday to Italy. It sounds marvellous- the cost of the flight, the hotel and all our meals are (37) _____ in the price. While we’re in Rome we’ll be going on a guided tour of the Coliseum. The last time I was in Italy, I was on a business trip – I can’t say I saw many of the famous tourist (38) _____ on that occasion

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:
After two decades of growing student enrollments and economic prosperity, business schools in the United States have started to face harder times. Only Harvard's MBA School has shown a substantial increase in enrollment in recent years. Both Princeton and Stanford have seen decreases in their enrollments. Since 1990, the number of people receiving Masters in Business Administration (MBA) degrees, has dropped about 3 percent to 75,000, and the trend of lower enrollment rates is expected to continue.
There are two factors causing this decrease in students seeking an MBA degree. The first one is that many graduates of four-year colleges are finding that an MBA degree does not guarantee a plush job on Wall Street, or in other financial districts of major American cities. Many of the entry-level management jobs are going to students graduating with Master of Arts degrees in English and the humanities as well as those holding MBA degrees. Students have asked the question, "Is an MBA degree really what I need to be best prepared for getting a good job?" The second major factor has been the cutting of American payrolls and the lower number of entry-level jobs being offered. Business needs are changing, and MBA schools are struggling to meet the new demands.

The word "prosperity" in line 1 could be best replaced by which of the following?

A. B.     C. D. 

Read the following passage and choose the best answer (A, B, C, D)
Amy Johnson was born in 1903 and grew up in Hull, England. The pioneering British aviator is one of the inspiring female figurehead of the 20th century. After university, Amy got a badly-paid (1)_____managed to save enough money to take flying lessons. She went on to qualify as a pilot, (2)___ receiving her license in 1929. In 1930, (3)_______only flown for seventy-five hours, she persuaded a rich businessperson to give her money to buy a plane, and set off alone for Darwin, Australia, in the hope of breaking the record for flying solo from England to Australia in fourteen days. Amy was the first woman to make this flight, (4) _______ took her nineteen days. She failed to breathe record, but was welcomed home as a hero. Over the next ten years, Amy made many record-breaking flights. During these years, she was admired for her skill and courage, and she is still fondly remembered as Britain’s first “Queen of the Air”. She is also remembered in many ways, one of which is the British Women Pilot’s Association award - a scholarship to help outstanding women pilots (5)______their careers

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Anna Gomez is a successful TV sports presenter, but most people still think of her as the famous women’s ice-skating champion who won several important competitions when she was younger. “As a child, my dream was actually to become a ballet dancer – I didn’t own any skates until I was nine, and didn’t become really keen on skating until I was fourteen,” says Anna. She went on to university, where, despite ice-skating almost all the time, she left with an excellent degree. “I felt I owed it to my parents. They supported me through university, and expected me to do well there – I didn’t feel I could disappoint them.” In a sport where most stars become famous as teenagers, Anna was unusual in being in her twenties before she won any major titles. “When I was younger, I got very angry at competitions, shouting at judges if I disagreed with them. That made me unpopular, especially with other skaters. My technique was just as good as theirs and I had a very encouraging coach at the time. The problem was in my head – I just didn’t think I had what it takes to be a champion. That changed as I won more competitions, and I was performing at my best by the age of twenty-five.” Anna retired from professional ice-skating five years later, having accomplished great success during that period. “It was a difficult decision. As you get near the end of your career, people always ask when you’re going to stop. At the time, I wasn’t sure that I was actually ready to give up. But, looking back, I’m glad I stopped when I did. You shouldn’t think too much about the past – just move on to the next thing.”  
2. What do we learn about Anna’s time at university?

Read the following passage and choose the best answer (A, B, C, D):
Generation gap refers to a vast difference in cultural norms between a younger generation and their elders. It’s a distressing thing for the phenomenon (1) ____ occurs around the world. The (2) ____ of communication, different views on certain problems and different attitudes towards life may cause the generation gap or even widen it. First, one of the major factors for this misunderstanding between two generations is that parents and children lack communication. Young people (3) ____ reveal their feelings to their parents, and often complain that their parents are out of (4) ____ with modern days, that they are dominant, that they do not trust their children to deal with crises, and that they talk too much about certain problems. So when young people meet some problems, they would rather (5) ____ to their classmates or their friends for help. The lack of communication widens the generation gap Another factor is that parents and their children see almost everything from different (6) ____. Take choosing career as an example. Parents generally believe it is their responsibility to plan the career for their children. Some hope their children will (7) ____ professions that will bring them greatest prestige and economic benefits. Some hope children will have a stable job with a regular income. But the youth may think they should be free to (8) ____ their own decisions as to their future career. Young people explain that true success is not a matter of money or position, instead, it is a matter of self-fulfillment. Finally, with the change of the world over decades, the attitude of the young has altered too. There are differences in (9) ____ matters as musical tastes, fashions, drug use, sex and politics between the young people and their elders. Nowadays long hair on young males is viewed as fashion by the young, but it is frequently considered a shocking act of rebellion against (10) ____ norms by parents

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English teenagers are to receive compulsory cooking lessons in schools. The idea is to encourage healthy eating to fight the country’s increasing obesity rate. It’s feared that basic cooking and food preparation skills are being lost as parents turn to pre-prepared convenience foods. Cooking was once regarded as an important part of education in England – even if it was mainly aimed at girls. In recent decades cooking has progressively become a minor activity in schools. In many cases the schools themselves have given up cooking meals in kitchens in the schools. But the rising level of obesity has led to a rethink about the food that children are given and the skills they should be taught. “What I want is to teach young people how to do basic, simple recipes like a tomato sauce, a bolognaise, a simple curry, a stir-fry – which they can use now at home and then in their later life”, said Ed Balls, the minister responsible for schools. The new lessons are due to start in September, but some school without kitchens will be given longer to adapt. There is also likely to be a shortage of teachers with the right skills, since the trend has been to teach food technology rather than practical cooking. Also the compulsory lessons for hands on cooking will only be one hour a week for one term. But the well-known cookery writer, Pru Leith, believes it will be worth it. “If we’d done this thirty years ago we might not have the crisis we have got now about obesity and lack of knowledge about food and so on. Every child should know how to cook, not just so that they’ll be healthy, but because it’s a life skill which a real pleasure”. The renewed interest in cooking is primarily a response to the level obesity in Britain which is among the highest in Europe, and according to government figures half of all Britons will be obese in 25 years if current trends are not stopped  
4. The underlined phrase “a bolognaise” in the passage probably means ____________

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There are many strange superstitions in the world. The most common one is related to black cats, (1) ____ are the source of hundreds of unlucky superstitions. It’s a sign of bad luck if they walk in front of you or you step on their tails. They even bring bad luck into a house if they sneeze inside! This superstition dates (2) ____ to the Middle Ages when they became associated with witches and evil spirits. Another common superstition is about walking under a ladder. A more (3) ____ explanation can be traced back to ancient Egypt. The early Egyptians believed that the shape of the Pyramids had a special power. It was considered very bad luck to break the “power” of this shape and that’s exactly what walking under a ladder would do! In addition, in Roman times, people (4) ____ the habit of looking at themselves in pools of water. Some believed that these reflections were in fact “glimpses of the soul”. Any disruption to the water in the pool would bring bad luck to the person looking in it. This superstition lives (5)_________the fear of bad luck from breaking a mirror

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People who do not smoke, are not obese, and consume alcohol moderately can expect to live seven years longer than the general population, and to spend most of these extra years in good health, according to a new study published today in Health Affairs. This study was the first to analyze the cumulative impact of several key health behaviours on disability-free and total life expectancy. Previous studies have looked at single health behaviours. Mikko Myrskylä and his colleague instead examined several behaviors simultaneously, which allowed them to determine how long and healthy the lives of people who had avoided most of the well-known individual behavioral risk factors were. The researchers noted that each of the three unhealthy behaviours – obesity, smoking, and unhealthy consumption of alcohol – was linked to a reduction in life expectancy and to an earlier occurrence of disabilities. But there were also differences: smoking was found to be associated with an early death but not with an increase in the number of years with disability, whereas obesity was shown to be associated with a long period of time with disability. Excessive alcohol consumption was found to be associated with both decreased lifespan and a reduced number of healthy years. However, the absence of all of these risky healthy behaviors was found to be associated with the greatest number of healthy years. The most striking finding was the discovery of a large difference in average lifespan between the groups who were the most and the least at risk. Men who were not overweight, had never smoked, and drank moderately were found to live an average of 11 years longer than men who were overweight, had smoked, and drank excessively. For women, the gap between these two groups was found to be even greater, at 12 years. “Our results show how important it is to focus on prevention. Those who avoid risky health behaviours are achieving very long and healthy lives. Effective policy interventions targeting health behaviors could help larger fractions of the population to achieve the health benefits observed in this study,” the researcher emphasized. These results are important not only for individuals, but also for society. In an aging society, the health of the elderly determines the amount of money spent on the health system. In addition, healthy elderly people are better able to participate in the labor market and to perform social roles, such as caring for grandchildren.  
5. The word “them” in paragraph 2 refers to _____

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Most languages have several levels of vocabulary that may be used by the same speakers. In English, at least three have been identified and described. Standard usage includes those words and expressions understood, used, and accepted by a majority of the speakers of a language in any situation regardless of the level of formality. As such, these words and expressions are well defined and listed in standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms that are understood by almost all speakers of a language and used in informal speech or writing, but not considered acceptable for more formal situations. Almost all idiomatic expressions are colloquial language. Slang, refers to words and expressions understood by a large number of speakers but not accepted as appropriate formal usage by the majority. Colloquial expressions and even slang may be found in standard dictionaries but will be so identified. Both colloquial usage and slang are more common in speech than writing. Colloquial speech often passes into standard speech. Some slang also passes into standard speech, but other slang expressions enjoy momentary popularity followed by obscurity. In some cases, the majority never accepts certain slang phrases but nevertheless retains them in their collective memories. Every generation seems to require its own set of words to describe familiar objects and events. It has been pointed out by a number of linguists that three cultural conditions are necessary for the creation of a large body of slang expressions. First, the introduction and acceptance of new objects and situations in the society; second, a diverse population with a large number of subgroups; third, association among the subgroups and the majority population. Finally, it is worth noting that the terms "standard", "colloquial", and "slang" exist only as abstract labels for scholars who study language. Only a tiny number of the speakers of any language will be aware that they are using colloquial or slang expressions. Most speakers of English will, during appropriate situations, select and use three types of expressions.
2. Which of the following is the main topic of the passage?

Books which give instructions on how to do things are very popular in the United States today. Thousands of these How-to books are useful. In fact, there are about four thousand books with titles that begin with the words “How to”. One book may tell you how to earn more money. Another may tell you how to save or spend it and another may explain how to give your money away.

Many How-to books give advice on careers. They tell you how to choose a career and ‘now to succeed in it. If you fail, however, you can buy the book ” How to Turn Failure into Success”. If you would like to become very rich, you can buy the book “How to Make a Millionaire”. If you never make any money at all, you may need a book called “How to Live on Nothing”.

One of the most popular types of books is one that helps you with personal problems. If you want to have a better love of life, you can read “How to Succeed in Love every Minute of Your Life”. If you are tired of books on happiness, you may prefer books which give step-by-step instructions on how to redecorate or enlarge a house.

Why have How-to books become so popular? Probably because life has become so complex. Today people have far more free time to use, more choices to make, and more problems to solve. How-to books help people deal with modern life.

The word “it” in paragraph 2 refers to _________

Choose the best answer:
“ Paul, where is …… Spanish dictionary? I’m writing an essay in Spanish and I need it.”

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With 13,000 floral species and over 15,000 faunal species, three newly discovered big animal species, and a ratio of country/world species of 6.3%. Vietnam has enormous tourismparticularly ecotourism-potential. In fact, since 1986, when Renovation Reforms began the shift from a centrally planned to a socialist-oriented market, or multi-sectoral, economy, tourism has been an sector of primary concern to the government. In May 1995, the prime minister of Vietnam approved a master plan of tourism development for the period 1995- 2010. In February 1999, the state decree on tourism was part of the socio-economic development strategy for the period 2001-2010 approved at the IX National Congress of the Party: “Tourism development has become a spearhead economic industry indeed. It is necessary to improve the quality and effectiveness of tourism activities, bringing into full play the natural conditions, and cultural and historical tradition to meet the domestic and international demand for tourism and to catch up with tourism development in the region” (Document of the IX National Congress 2001). Tourism has so far brought great benefits to the economy, but it has also contributed to environmental degradation, especially biodiversity deterioration. Thus, the concept of “sustainable development”-development which meets the needs of the present without compromising the ability of future generations to meet their own needs - must be factored into tourism development. This consideration is reflected in the term “ecotourism,” which is referred to variously as ecological or environmental tourism, nature or green tourism, sustainable or responsible tourism. Ecotourism involves travel to relatively undisturbed natural areas with the specific object of studying, admiring, and enjoying scenery, plants, and animals, as well as any cultural features found in these areas. It is distinguished from mass or resort tourism by its lower impact on the environment, lower infrastructure requirements, and its role in educating tourists about natural environments and cultural values. Fully aware of its significance, the government of Vietnam has prioritized ecotourism in its strategy for tourism development to ensure both sustainability and economic benefits. Though ecotourism in Vietnam is at a beginning stage of development, it is expected to grow strongly through support from government and international organizations.  
3. It can be inferred that in the late 20th century Vietnam’s tourism ____.

Read the following passage and choose the best answer (A, B, C, D):
With 13,000 floral species and over 15,000 faunal species, three newly discovered big animal species, and a ratio of country/world species of 6.3%. Vietnam has enormous tourismparticularly ecotourism-potential. In fact, since 1986, when Renovation Reforms began the shift from a centrally planned to a socialist-oriented market, or multi-sectoral, economy, tourism has been an sector of primary concern to the government. In May 1995, the prime minister of Vietnam approved a master plan of tourism development for the period 1995- 2010. In February 1999, the state decree on tourism was part of the socio-economic development strategy for the period 2001-2010 approved at the IX National Congress of the Party: “Tourism development has become a spearhead economic industry indeed. It is necessary to improve the quality and effectiveness of tourism activities, bringing into full play the natural conditions, and cultural and historical tradition to meet the domestic and international demand for tourism and to catch up with tourism development in the region” (Document of the IX National Congress 2001). Tourism has so far brought great benefits to the economy, but it has also contributed to environmental degradation, especially biodiversity deterioration. Thus, the concept of “sustainable development”-development which meets the needs of the present without compromising the ability of future generations to meet their own needs - must be factored into tourism development. This consideration is reflected in the term “ecotourism,” which is referred to variously as ecological or environmental tourism, nature or green tourism, sustainable or responsible tourism. Ecotourism involves travel to relatively undisturbed natural areas with the specific object of studying, admiring, and enjoying scenery, plants, and animals, as well as any cultural features found in these areas. It is distinguished from mass or resort tourism by its lower impact on the environment, lower infrastructure requirements, and its role in educating tourists about natural environments and cultural values. Fully aware of its significance, the government of Vietnam has prioritized ecotourism in its strategy for tourism development to ensure both sustainability and economic benefits. Though ecotourism in Vietnam is at a beginning stage of development, it is expected to grow strongly through support from government and international organizations.  
2. When has tourism officially contributed to socio-economic development?

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometres in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the tune it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word "radar" in fact gets its name from the term "radio detection and ranging". "Ranging" is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots radar is essential for air traffic control tracking ships at sea, and for tracking weather Systems and storms

The word "tracking" in the passage most closely means...............................