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. 
Coral reefs are some of the most diverse ecosystems in the world, housing tens of thousands of marine species. With their hardened surfaces, corals are sometimes mistaken as being rocks. And, because they are attached, “taking root” to the seafloor, they are often mistaken for plants. However, unlike rocks, corals are alive. And unlike plants, corals do not make their own food. Corals are in fact animals. Appearing as solitary forms in the fossil record more than 400 million years ago, corals are extremely ancient animals that evolved into modern reef-building forms over the last 25 million years.
Coral reefs are the largest structures on earth of biological origin. Coral reefs are unique and complex systems. Rivaling old growth forests in longevity of their ecological communities, well-developed reefs reflect thousands of years of history.
Corals are ancient animals related to jellyfish and anemones. The branch or mound that we often call “a coral” is actually made up of thousands of tiny animals called polyps. A coral polyp is an invertebrate that can be no bigger than a pinhead to up to 30 centimeters (1 foot) in diameter. The polyps extend their tentacles at night to sting and ingest tiny organisms called plankton and other small creatures. Each polyp has a saclike body and a mouth that is encircled by stinging tentacles. The polyp uses calcium carbonate (limestone) from seawater to build a hard, cup-shaped skeleton. This skeleton protects the soft, delicate body of the polyp.
Reefs only occur in shallow areas that are reachable by sunlight because of the relationship between coral and algae. Various types of microscopic algae, known as Symbiodinium, live inside of the coral, providing them with food and helping them to grow faster.
There are over 2,500 kinds (species) of corals. About 1,000 are the hard corals that build coral reefs. Other corals are soft corals. Soft corals have skeletons that are flexible and can bend with the water. The three main types of coral reefs are fringing reefs, barrier reefs, and coral atolls. The most common type of reef is the fringing reef. This type of reef grows seaward directly from the shore. They form borders along the shoreline and surrounding islands. When a fringing reef continues to grow upward from a volcanic island that has sunk entirely below sea level, an atoll is formed. Atolls are usually circular or oval in shape, with an open lagoon in the center. Any reef that is called a barrier reef gets its name because its presence protects the shallow waters along the shore from the open sea. That protection promotes the survival of many types of sea plant and animal life.

According to the passage, the following are true about coral reefs, EXCEPT ____________.

Psychologists have debated a long time about whether a child's upbringing can give it the ability to do outstandingly well. Some think that it is impossible to develop genius and say that it is simply something a person is born with. Others, however, argue that the potential for great achievement can be developed. The truth lies somewhere between these two extremes.
It seems very obvious that being born with the right qualities from gifted parents will increase a child's ability to do well. However, this ability will be fully realized only with the right upbringing and opportunities. As one psychologist says, "To have a fast car, you need both a good engine and fuel.” Scientists have recently assessed intelligence, achievement, and ability in 50 sets of identical twins that were separated shortly after birth and brought up by different pa rents. They found that achievement was based on intelligence, and later influenced by the child's environment
One case involving very intelligent twins was quoted. One of the twins received a normal upbringing, and performed well. The other twin, however, was brought up by extremely supportive parents and given every possible opportunity to develop its abilities. That twin, though starting out with the same degree of intelligence as the other, performed even better.
This case reflects the general principle of intelligence and ability. The more favorable the environment, the more a child's intelligence and ability are developed. However, there is no link between intelligence and the socioeconomic level of a child's family.  In other words, it does not matter how poor or how rich a family is, as this does not affect intelligence.
Gifted people cannot be created by supportive parents, but they can be developed by them.
One professor of music said that outstanding musicians usually started two or three years earlier than ordinary performers, often because their parents had recognized their ability. These musicians then needed at least ten years' hard work and training in order to reach the level they were capable of attaining.
People who want to have very gifted children are given the following advice:
- Marry an intelligent person.
- Permit children to chase their own interests rather than the interests of the parents.
- Start a child's education early but avoid pushing the child too hard.
- Encourage children to play; for example, playing with musical instruments is essential for a child who wants to become an outstanding musician.

How were great musicians different from ordinary musicians in their development?

Read the text below and decide which answer (A,B,C, or D) best fits each space. 
BICYCLES
Why don’t the British cycles? Only a quarter of the estimated twenty million bicycles in the country are thought to be in (58) …….. use. In Denmark, which is flatter but no darker  or  rainier  than  Britain,  twenty  percent  of  all  journeys  are  made  by  bicycles, while in Britain the (59) …….. is only 5%. The government are trying to (60) …….. this. It is hoped that a grant of millions of pounds from the National Lottery will (61)…….. more people to use their bikes. The money will be used to (62) …….. for a 6,500 mile national network of cycle tracks. Britain needs to (63) …….. environmentally friendly scheme such as this. The southern third of the country is one of the most (64)…….. areas of the world. Environmentalists make it (65) …….. to build new roads, and (66)  ……..  roads  are  overcrowded.  One  official  committee  described  the  growth  of motor transport as “possibly the (67) ……. environmental threat to the UK”. The (68)…….. of building the cycles tracks is to motivate people to use their bicycles instead of their cars. However, the new tracks are being built (69) …….. cities and not through them. This (70) …….. that only long distance journeys may be easier and safer. Those cyclists who want to (71) …….. inside cities will still be in danger of (72) …….. their lives on busy roads every time they use their bicycles.

60................

Giải thích: improve (v): cải thiện, cải tiện

Những đáp án còn lại:

A.  Succeed (v): thành công

C.  Excel (v): trội hơn

D.  Help (v): giúp đỡ

Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine, Beyond these simple and direct uses, those forms have not much adaptability.
On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator,   and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a  cup of coffee. Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances.
To generate electricity, huge turbines or generators must be turned. In  Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation.
Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels.

The main forms of power used to generate electricity in Australia are ..................

Fill in each numbered blank with one suitable word or phrase.

That is a program of Ho Chi Minh City Youth Union to (1) _____ individuals, domestic and foreign organizations buy and use bicycles during the time (2) _____ they enjoy the SEA Games 22 in Ho Chi Minh City then donate the bicycles to poor children. Preparing (3) _____ this program, the Organizing Committee has signed a (4) _____ with Martin- a bicycle-making firm - to purchase 1,000 bicycles, at prices from 850,000 to 1,000,000 VND per bicycle -10% (5) _____ than market prices, with nearly 20 different models. In the mid of November, The Organizing Committee will announce, promote, and (6) _____ the program "SEA Games Iron Horses - For Poor Children" through (7) _____ at airport, on buses, taxis, at information desks, posters, banners, newspapers, and websites of city Youth Union. Besides 1,200 volunteers (8) _____ the SEA Games 22, the Organizing Committee also recruits 100 active volunteers for this program to handle the handover and receiving bikes, instructing participating tourists, giving (9) _____ to questions through hot lines. This program both conveys practical significance and helps international friends to understand further the nation and people of Viet, Nam as well as strengthen the friendship and (10) _____ among nations.

(6) _____

Choose the letter A, B, C or D to answer these following questions

Games and sports are an important and essential part of a person's life. Along with the study, games, and sports are also important. Hence, most schools conducts various games competitions and sports. Along with the mental development of every person, physical development is also which needs to be taken into consideration. Sports is an important part of a student’s life as well. So, what is the importance of sports and games?

Sports gives us a good exercise which makes us physically strong and increases our stamina and strength. Regular sports activities make us active and lead to good health. Playing Games makes us aware of our environment i.e. Makes us mentally awake and increases our concentration power. Various Games needs good strategies for better performance and teamwork, so it increases our thinking ability and teaches us the power of teamwork and to find a way out of difficult situations. Games and sports also need a lot of energy. It makes us energetic. Games and Sports needs a lot of cooperation between the players. Hence it increases cooperation with each other.

And at last, all of the games have their own rules and regulations which if not followed, leads to negative points. Hence, we can say that it teaches us the importance of following rules in life.

What is the passage mainly about?

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 best explainer videos are realized by great background score. When was the last time you watched a silent movie? Never? Not for a while? A long while? Even if you remember watching one, it would still have had a background score, or you’ve accidentally pressed the mute button!
The importance of background music and sound effects for your explainer video, therefore, cannot be overstated. You may not need a full blown orchestra or classy jazz tones to create the mood, but whether going for a subtle effect, a professional demonstration or simply trying to attract customers, music is a must. Explainer videos have the emotional quotient working for them and music is just going to add more to make the viewers relate to the pain points you are highlighting in your video. Imagine if your favorite video game has no background music or sound effects to back the amazing graphics? Would you play it with the same feel and excitement? Nah! Same is the case with your explainer videos. They need to and should have apt sound effects to make them worth your viewer’s time.
While the focus of explainer videos production is more on passing the desired information and explaining technical and complex procedures easily, it doesn’t mean you’ll be distracting your viewers with the background music. The sound effects and music is not going to take the message away from your explainer, it’s just going to enhance it and turn it more watchable and share-able. Even if your video doesn’t require a background score, it must include some sound effects or else it would be not so good an experience for those who choose to watch it

Which best serves as the title for the passage?

Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. One adaptation is to be light in color,  and to reflect rather than absorb the Sun's rays. Desert mammals also depart from the normal mammalian practice of maintaining a constant body temperature. Instead of trying to keep down the body temperature deep inside the body, which would involve the expenditure of water and energy,  desert mammals allow their temperatures to rise to what would normally be fever height, and temperatures as high as 46 degrees Celsius have been measured in Grant's gazelles. The overheated body then cools down during the cold desert night, and indeed the temperature may fall unusually low by dawn,  as low as 34 degrees Celsius in the camel. This is an advantage since the heat of the first few hours of daylight is absorbed in warming up the body, and an excessive buildup of heat does not begin until well into the day.

Another strategy of large desert animals is to tolerate the loss of body water to a point that would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight as water without harm to itself, whereas human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to replenish this water loss at one drink. Desert animals can drink prodigious volumes in a short time, and camels have been known to imbibe over 100 liters in a few minutes. A very dehydrated person, on the other hand, cannot drink enough water to rehydrate at one session, because the human stomach is not sufficiently big and because a too rapid dilution of the body fluids causes death from water intoxication. The tolerance of water loss is of obvious advantage in the desert, as animals do not have to remain near a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the further ability to feed normally when extremely dehydrated, it is a common experience in people that appetite is lost even under conditions of moderate thirst.

What causes water  intoxication?

 Choose the item among A, B, C or D that best answers the question about the passage:

"The 22nd SEA Games were launched by an impressive opening ceremony at Hanoi’s My Dinh National Stadium on December 5th 2003, in front of over 40,000 awed spectators. On behalf of the host country, Prime Minister Phan Van Khai declared the 22nd SEA Games open.
 Deputy Prime Minister Pham Gia Khiem, Chairman of the National Steering Board for the 22nd SEA Games, Minister-Chairman Nguyen Danh Thai, and Hanoi Mayor Hoang Van Nghien presented flowers and banners to the 11 participating sports delegations.
 On behalf of the referees and athletes, referee Hoang Quoc Vinh and shooter Nguyen Manh Tuong swore to an oath of “Solidarity, Honesty and Fair Play”.After the “ritual” part of the ceremony, a laser light show kicked off the “festival” segment. More than one thousand artists, dressed in green and sea blue representing the forest and the sea, then presented the first chapter of the performance, named “The Land of the Dragon and Fairy”.
 The scene depicted the legend of Vietnam’s origins, featuring the father-Dragon and mother-Fairy, and ended with young men and women lining up in an S-shaped pattern, a Symbol of Vietnam as a country.
 The second part of the programme, named “Cooperation for Peace” featured children holding five pointed-stars and entering from the stadium's four gates, representing Hanoi, the Capital City with one thousand years of history.
 Dancing men and women in traditional costumes of ASEAN members and East Timor concluded the third segment, named “United ASEAN Looks To The Future”, which comprised four performances: “Lands by the Pacific Ocean,” “Essential Convergence,” “New Tune,” and “ASEAN Towards The Future.”
 The Games mascot, the Golden Buffalo, and 22 singers (standing for the 22nd Games) then took centre stage, singing the Games official song “For a World of Tomorrow”. The whole show ended as thousands of flying balls were released and fireworks were fired from four places in Hanoi."

3. The festival performances of the opening ceremony included …….

Mark the letter A, B, C or D to indicate the underlined part that needs correction in each of the following questions.

Down did an apple fall when he was passing under the tree.

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. 
Human beings are extremely diverse in very many ways. People differ (23) ____ opinions, race, nationality, gender, age, sexuality, ethnicity, class, religion, lifestyle and so much more, yet at the very basic we are all human species. Ideally, all people feel (24) ____ and joy despite the differences. Today, the changes in time and technology have made is extremely impossible for any group of people to live without interacting with others outside their group. Often people of different cultural and geographical (25) ____ meet in international conferences, education exchange programs, sports, etc.
Sadly, the history of mankind discriminating against each other based on cultural differences has been with us for ages. So many people have died or have been denied their rights (26) _________ individual greed. Properties and economies have also been destroyed due to lack of understanding. Unfortunately, some of these occurrences are visible even today, perpetuated by people who little understand the importance of the (27)__________of our diversity.

Often people of different cultural and geographical (25) ____ meet in international conferences,

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.

   A rather surprising geographical feature of Antarctica is that a huge freshwater lake, one of the world’s largest and deepest, lies hidden there under four kilometers of ice. Now known as Lake Vostok, this huge body of water is located under the ice block that comprises Antarctica. The lake is able to exist in its unfrozen state beneath this block of ice because its waters are warmed by geothermal heat from the earth’s core. The thick glacier above Lake Vostok actually insulates it from the frigid temperatures on the surface.

   The lake was first discovered in the 1970s while a research team was conducting an aerial survey of the area. Radio waves from the survey equipment penetrated the ice and revealed a body of water of indeterminate size. It was not until much more recently that data collected by satellite made scientists aware of the tremendous size of the lake; the satellite-borne radar detected an extremely flat region where the ice remains level because it is floating on the water of the lake.

   The discovery of such a huge freshwater lake trapped under Antarctica is of interest to the scientific community because of the potential that the lake contains ancient microbes that have survived for thousands of years, unaffected by factors such as nuclear fallout and elevated ultraviolet light that have affected organisms in more exposed areas. The downside of the discovery, however, lies in the difficulty of conducting research on the lake in such a harsh climate and in the problems associated with obtaining uncontaminated samples from the lake without actually exposing the lake to contamination. Scientists are looking for possible ways to accomplish this.

The word “microbes” in paragraph 3 could best be replaced by which of the following?

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 best explainer videos are realized by great background score. When was the last time you watched a silent movie? Never? Not for a while? A long while? Even if you remember watching one, it would still have had a background score, or you’ve accidentally pressed the mute button!
The importance of background music and sound effects for your explainer video, therefore, cannot be overstated. You may not need a full blown orchestra or classy jazz tones to create the mood, but whether going for a subtle effect, a professional demonstration or simply trying to attract customers, music is a must. Explainer videos have the emotional quotient working for them and music is just going to add more to make the viewers relate to the pain points you are highlighting in your video. Imagine if your favorite video game has no background music or sound effects to back the amazing graphics? Would you play it with the same feel and excitement? Nah! Same is the case with your explainer videos. They need to and should have apt sound effects to make them worth your viewer’s time.
While the focus of explainer videos production is more on passing the desired information and explaining technical and complex procedures easily, it doesn’t mean you’ll be distracting your viewers with the background music. The sound effects and music is not going to take the message away from your explainer, it’s just going to enhance it and turn it more watchable and share-able. Even if your video doesn’t require a background score, it must include some sound effects or else it would be not so good an experience for those who choose to watch it

According to paragraph 2, what is the main purpose for using background music?

Read the passage Carefully, then choose the correct answer. 
The Southeast Asian Games owes its origins to the Southeast Asian Peninsular Games or SEAP Games. On May 22, 1958, delegates from the countries in Southeast Asian peninsula attending the 3rd Asian Game's in Tokyo, Japan had a meeting and agreed to establish a sport organization. The SEAP Games was conceptualized by Laung Sukhumnaipradit, then Vice-President of the Thailand Olympic Committee. The proposed rationale was that a regional sports event will help promote cooperation, understanding and relations among countries in the Southeast Asian region.
Thailand, Myanmar, Malaysia, Laos, Vietnam and Cambodia (with Singapore Included thereafter) were the founding members. These countries agreed to hold the Games biennially. The SEAP Games Federation Committee was formed.
The first SEAP Games were held in Bangkok from 12-17 December , 1959 comprising more than 527 athletes and officials from Thailand, Myanmar, Malaysia, Singapore, South Vietnam and Laos participating in 12 sports. 
At the 8th SEAP Games in 1975, the SEAP Federation considered the inclusion of Indonesia and the Philippines. The two countries were formally admitted In 1977, the same year when SEAP Federation changed their name to Southeast Asian Games Federation (SEAGF), and the games were known as the Southeast Asian Games. Brunei was admitted at the 10th SEA Game in Jakarta, Indonesia, and East Timor at the 22nd SEA Games in Hanoi, Vietnam. 
The 2007 Southeast Asian Games were held in the Thailand, which started from 6 December and ended on 15 December 2007, hosting the biennial event for the sixth time and it was also the most protested SEAG ever. The next host for the SEA Games is Laos. It is Laos' first time at the host for the biannual games.

Which of the following is NOT true?

Fill in each numbered blank with one suitable word or phrase.

That is a program of Ho Chi Minh City Youth Union to (1) _____ individuals, domestic and foreign organizations buy and use bicycles during the time (2) _____ they enjoy the SEA Games 22 in Ho Chi Minh City then donate the bicycles to poor children. Preparing (3) _____ this program, the Organizing Committee has signed a (4) _____ with Martin- a bicycle-making firm - to purchase 1,000 bicycles, at prices from 850,000 to 1,000,000 VND per bicycle -10% (5) _____ than market prices, with nearly 20 different models. In the mid of November, The Organizing Committee will announce, promote, and (6) _____ the program "SEA Games Iron Horses - For Poor Children" through (7) _____ at airport, on buses, taxis, at information desks, posters, banners, newspapers, and websites of city Youth Union. Besides 1,200 volunteers (8) _____ the SEA Games 22, the Organizing Committee also recruits 100 active volunteers for this program to handle the handover and receiving bikes, instructing participating tourists, giving (9) _____ to questions through hot lines. This program both conveys practical significance and helps international friends to understand further the nation and people of Viet, Nam as well as strengthen the friendship and (10) _____ among nations.

(5) _____

Read the passage and choose the best answer:

 History of SEA Games

The Southeast Asian Games owes its origins to the Southeast Asian Peninsular Games or SEAP Games. On 22 May, 1958, delegates from the countries in Southeast Asian Peninsula attending the 3rd Asian Games in Tokyo, Japan had a meeting and agreed to establish a sport organization. The SEAP Games was conceptualized by Laung Sukhumnaipradit, then Vice-President of the Thailand Olympic Committee. The proposed rationale was that a regional sports event will help promote cooperation, understanding and relations among countries in the Southeast Asian Peninsula region. Thailand, Burma (now Myanmar), Malaya (now Malaysia), Laos, South Vietnam (now Vietnam) and Cambodia were the founding members. These countries agreed to hold the Games biannually. The SEAP Games Federation Committee was formed.

The first SEAP Games were held in Bangkok from 12-17 December, 1959 comprising more than 527 athletes and officials from Thailand, Burma, Malaysia, Cambodia, South Vietnam and Laos participating in 12 sports. At the 8th SEAP Games in 1975, the SEAP Federation considered the inclusion of Indonesia and the Philippines. The two countries were formally admitted in 1977, the same year when SEAP Federation changed their name to Southeast Asian Games Federation (SEAGF), and the games were known as the Southeast Asian Games. Brunei was admitted at the 9th SEA Games in Kualalumper, Malaysia, and East Timor at the 22nd SEA Games in Hanoi, Vietnam. The 23rd SEA Games held in the Philippines, which started from 27 November and ended on 5 December 2005, hosting the biennial event for the third time.

The 24th SEA Games was held in 2007.

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

   In developing countries, where three fourths of the world's population live, sixty percent of the people who can’t read and write are women. Being illiterate doesn’t mean they are not intelligent. It does mean it is difficult for them to change their lives. They produce more than half of the food. In Africa eighty percent of all agricultural work is done by women. There are many programs to help poor countries develop their agriculture. However, for years, these programs provided money and training for men.

   In parts of Africa, this is a typical day for a village woman. At 4:45 a.m, she gets up, washes and eats. It takes her a half hour to walk to the fields, and she works there until 3:00 p.m. She collects firewood and gets home at 4:00. She spends the next hour and a half preparing food to cook. Then she collects water for another hour. From 6:30 to 8:30 she cooks. After dinner, she spends an hour washing the dishes and her children. She goes to bed at 9:30 p.m.

   International organizations and programs run by developed nations are starting to help women, as well as men, improve their agricultural production. Governments have already passed some laws affecting women because of the UN Decade for Women. The UN report will affect the changes now happening in the family and society.

Which of these statements is NOT TRUE?

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

"The 22nd SEA Games were launched by an impressive opening ceremony at Hanoi’s My Dinh National Stadium, in front of over 40,000 awed spectators. Divided into two parts, rites and festivals, the ceremony (1)…. At 19:00 with the song, “Vietnam - Our Fatherland”. The (2)….. appearance of parachutists, carrying the 11 national flags of the competing Southeast Asian countries, was greeted (3) …. thunderous applause from the audience.
 All the stadium’s lights suddenly came on, (4)…. the start of the procession of Vietnam’s flag and the 22nd SEA Games' Symbol. The 11 sporting delegations then marched past the reviewing stand to excite applause from officials and spectators.
 The sacred torch, which symbolises the (5)….. of the Games and (6)… to compete with burning intensity, was taken from the Ho Chi Minh Museum and passed by Truong Quoc Thang (cyclist), Bui Thi Nhung (runner), Vu Kim Anh (karate artist) and athletes from 10 regional countries to Nguyên Thuy Hien (wushu artist) (7)….. gave it to the Prime Minister, who in tum passed it to an athlete dressed like national hero Giong.
 From this athlete’s hand, the official flame was lit at My Dinh National Stadium and will bum (8) …… the course of the Games. (9)……  at the opening ceremony, Minister-Chairman of the Physical Training and Sports Committee Nguyen Danh Thai, who is also the head of the 22nd SEA Games Organising Board, warmly welcomed Party and State leaders, delegates, domestic and international guests, and 11 sports delegations from Southeast Asian countries to the 22nd SEA Games.
 (10)…….  behalf of the host country, Prime Minister Phan Van Khai declared the 22nd SEA Games open."

3. was greeted (3) …. thunderous applause from the audience.

American music, in most of its various forms, can be traced back to the music of the  earliest African- Americans. Even though these Americans came here under the worst of  circumstances, they still brought with them traditions, and developed new traditions of their own, that have grown into what is recognized around the world today as American music. 

Musicians, like other artists, are usually quick to give credit where credit is due. Just as a  writer quotes his sources, a musician credits those musicians who inspired him. In the case of the  early African-Americans, that is not always easy. Many of the slaves who brought musical  traditions from Africa will never be known by name. No one wrote their history. Many of the slaves who sang work songs in the fields will never be known by name. No one wrote their history either. 

However, there is a lot that we do know. 

The first well-recognized form of African-American music was spirituals. Spirituals are religious songs. They are songs that tell a story or express emotions. Spirituals have a strong  rhythm. They are often sung by a group, sometimes with a leader who sings a line or two alone and a chorus that sings the refrain. Spirituals originated in the Southern United States. Spirituals sung by slaves often expressed the hope for freedom that was so important in their lives. Well know spirituals include "Go Down Moses," "Deep River," and "Swing Low SweetChariot." After slavery ended, spirituals began to spread to other parts of the United States. Harry  Thacker Burleigh was one of the first singers to perform spirituals on stage in a concert. Marian Anderson, well known for her classical singing, helped spirituals to gain a wider audience too.  Spirituals influenced the development of another well-known form of American music - the blues. The blues were a more individual style of music than spirituals. Blues were often sung  solo, and sometimes they were accompanied by guitar music. As the name suggests, the blues were often about sadness and facing troubles. However, the blues could also be funny, positive, and  even defiant. One blues singer, loved for her strong, beautiful voice, was Bessie Smith. Another  early blues musician was W. C. Handy. Handy was not only a musician, he also wrote music,  promoted concerts, and published bluessongs. 

During the time that the blues were spreading across the country, another style of music  was also quickly gaining in popularity. Ragtime was energetic music with a complicated,  syncopated beat. Often played on the piano, ragtime was the latest and most sophisticated in American popular music. The best-known  ragtime musician was probably Scott Joplin, who wrote many hit ragtime pieces for the piano  including "Maple Leaf Rag." 

Eventually, elements from all of these forms of music and more came back together. In  their own kind of melting pot, African rhythms, slave work songs, spirituals, blues, ragtime, and  other influences recombined to form the beginnings of that truly American art form - jazz. In the late 1800’s jazz was just beginning, but not long after the turn of the century, it would be the most popular American music. It would go on from there to worldwide popularity. Jazz would branch  out into many forms, and it would influence future styles of Americanmusic. 

Many musicians today credit earlier musicians such as Scott Joplin or Bessie Smith with inspiring their music. It’s a shame that they can’t also name the earliest African-Americans who  really began the traditions that led to the American music of today.

What is the closest meaning to the word “chorus” used in the passage?

Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine, Beyond these simple and direct uses, those forms have not much adaptability.
On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator,   and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a  cup of coffee. Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances.
To generate electricity, huge turbines or generators must be turned. In  Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation.
Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels.

What does the author mean by saying that electricity is flexible?