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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 from 33 to 37. Fill in the appropriate word in question 33 AS OLD AS YOU FEEL It might after all be true that you are only as old as you feel. A British clinic is carrying out new high-tech tests to calculate the “real” biological age of patients (33) ______ on the rate of physical deterioration. Information on every aspect of a patient’s health, fitness, lifestyle and family medical history is (34) ______ into a computer to work out whether they are older or younger than their calendar age suggests. The availability and increasing accuracy of the tests has prompted one leading British gerontologist to call for biological age to be used to determine when workers should retire. He (35) ______ that if an employee’s biological or “real” age is shown, for example, to be 55 when he reaches his 65th birthday, he should be incited to work for another decade. Apparently most employers only take into (36) ______ a person’s calendar years, and the two may differ considerably. Some of those prepared to pay a substantial sum of money for the examinations will be able to smugly walk away with medical evidence showing that they really are as young as they feel, giving them the confidence to act and dress as if they were younger. Dr Lynette Yong, resident doctor at the clinic where the tests are offered claims that the purpose of these tests will be to motivate people to (37) _______ their health. The concept of “real” age is set to become big business in the USA with books and websites helping people work out whether their body is older or younger than their years. Others firmly believe that looks will always be the best indicator of age. 

Xem chi tiết 2.4 K lượt xem 5 năm trước

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 below. Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing (as far as we can tell from surviving evidence) for at least 5000 years; but they have been talking for much longer, doubtless ever since there have been human beings. When writing did develop, it was derived from and represented speech, although imperfectly. Even today there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any human child who is not severely handicapped physically or mentally will learn to talk. a normal human being cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write. In the past many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write, while some who learn the rudiments of those skills do so only imperfectly. To affirm the primacy of speech over writing is not, however, to disparage the latter. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized. The author of the passage argues that ______.

Xem chi tiết 1.5 K lượt xem 5 năm trước

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 below. Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing (as far as we can tell from surviving evidence) for at least 5000 years; but they have been talking for much longer, doubtless ever since there have been human beings. When writing did develop, it was derived from and represented speech, although imperfectly. Even today there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any human child who is not severely handicapped physically or mentally will learn to talk. a normal human being cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write. In the past many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write, while some who learn the rudiments of those skills do so only imperfectly. To affirm the primacy of speech over writing is not, however, to disparage the latter. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized. We sometimes think of writing as more real than speech because ______.

Xem chi tiết 589 lượt xem 5 năm trước

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 from 33 to 37. Fill in the appropriate word in question 35 AS OLD AS YOU FEEL It might after all be true that you are only as old as you feel. A British clinic is carrying out new high-tech tests to calculate the “real” biological age of patients (33) ______ on the rate of physical deterioration. Information on every aspect of a patient’s health, fitness, lifestyle and family medical history is (34) ______ into a computer to work out whether they are older or younger than their calendar age suggests. The availability and increasing accuracy of the tests has prompted one leading British gerontologist to call for biological age to be used to determine when workers should retire. He (35) ______ that if an employee’s biological or “real” age is shown, for example, to be 55 when he reaches his 65th birthday, he should be incited to work for another decade. Apparently most employers only take into (36) ______ a person’s calendar years, and the two may differ considerably. Some of those prepared to pay a substantial sum of money for the examinations will be able to smugly walk away with medical evidence showing that they really are as young as they feel, giving them the confidence to act and dress as if they were younger. Dr Lynette Yong, resident doctor at the clinic where the tests are offered claims that the purpose of these tests will be to motivate people to (37) _______ their health. The concept of “real” age is set to become big business in the USA with books and websites helping people work out whether their body is older or younger than their years. Others firmly believe that looks will always be the best indicator of age. 

Xem chi tiết 884 lượt xem 5 năm trước

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 from 33 to 37. Fill in the appropriate word in question 34 AS OLD AS YOU FEEL It might after all be true that you are only as old as you feel. A British clinic is carrying out new high-tech tests to calculate the “real” biological age of patients (33) ______ on the rate of physical deterioration. Information on every aspect of a patient’s health, fitness, lifestyle and family medical history is (34) ______ into a computer to work out whether they are older or younger than their calendar age suggests. The availability and increasing accuracy of the tests has prompted one leading British gerontologist to call for biological age to be used to determine when workers should retire. He (35) ______ that if an employee’s biological or “real” age is shown, for example, to be 55 when he reaches his 65th birthday, he should be incited to work for another decade. Apparently most employers only take into (36) ______ a person’s calendar years, and the two may differ considerably. Some of those prepared to pay a substantial sum of money for the examinations will be able to smugly walk away with medical evidence showing that they really are as young as they feel, giving them the confidence to act and dress as if they were younger. Dr Lynette Yong, resident doctor at the clinic where the tests are offered claims that the purpose of these tests will be to motivate people to (37) _______ their health. The concept of “real” age is set to become big business in the USA with books and websites helping people work out whether their body is older or younger than their years. Others firmly believe that looks will always be the best indicator of age. 

Xem chi tiết 811 lượt xem 5 năm trước

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 from 33 to 37. Fill in the appropriate word in question 33 AS OLD AS YOU FEEL It might after all be true that you are only as old as you feel. A British clinic is carrying out new high-tech tests to calculate the “real” biological age of patients (33) ______ on the rate of physical deterioration. Information on every aspect of a patient’s health, fitness, lifestyle and family medical history is (34) ______ into a computer to work out whether they are older or younger than their calendar age suggests. The availability and increasing accuracy of the tests has prompted one leading British gerontologist to call for biological age to be used to determine when workers should retire. He (35) ______ that if an employee’s biological or “real” age is shown, for example, to be 55 when he reaches his 65th birthday, he should be incited to work for another decade. Apparently most employers only take into (36) ______ a person’s calendar years, and the two may differ considerably. Some of those prepared to pay a substantial sum of money for the examinations will be able to smugly walk away with medical evidence showing that they really are as young as they feel, giving them the confidence to act and dress as if they were younger. Dr Lynette Yong, resident doctor at the clinic where the tests are offered claims that the purpose of these tests will be to motivate people to (37) _______ their health. The concept of “real” age is set to become big business in the USA with books and websites helping people work out whether their body is older or younger than their years. Others firmly believe that looks will always be the best indicator of age. 

Xem chi tiết 1.8 K lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. The phrase “put aside” in the second paragraph is closet in meaning to _____.

Xem chi tiết 742 lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. According to the passage, the emergence of a business community in the colonies was a result of _____.

Xem chi tiết 620 lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. According to the passage, capital includes all of the following EXCEPT _____.

Xem chi tiết 1.8 K lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. The word “it” in the third sentence of paragraph 2 refers to _____.

Xem chi tiết 762 lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. According to the passage, which of the following would lead to accumulating capital?

Xem chi tiết 536 lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. It can be inferred from the passage that the European ancestors of early Americans ______.

Xem chi tiết 505 lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. The phrase “paved the way” in the second paragraph is closest in meaning to ______.

Xem chi tiết 3 K lượt xem 5 năm trước

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. “The economic history of the United States”, one scholar has written, “is the history of the rise and development of the capitalistic system”. The colonists of the eighteenth century pushed forward what those of the seventeenth century have begun: the expansion and elaboration of an economy born in the great age of capitalist expansion. Our excellent natural resources paved the way for the development of abundant capital to increase our growth. Capital includes the tools – such as: machines, vehicles, and buildings – that makes the outputs of labor and resources more valuable. But it also includes the funds necessary to buy those tools. If a society had to consume everything it produced just to stay alive, nothing could be put aside to increase future productions. But if a farmer can grow more corn than his family needs to eat, he can use the surplus as seed to increase the next crop, or to feed workers who build tractors. This process of capital accumulation was aided in the American economy by our cultural heritage. Saving played an important role in the European tradition. It contributed to American’s motivation to put something aside today for the tools to buy tomorrow. The great bulk of the accumulated wealth of America, as distinguished from what was consumed, was derived either directly or indirectly from trade. Though some manufacturing existed, its role in the accumulation of capital was negligible. A merchant class of opulent proportions was already visible in the seaboard cities, its wealth as the obvious consequence of shrewd and resourceful management of the carrying trade. Even the rich planters of tidewater Virginia and the rice coast of South Carolina finally depended for their genteel way of life upon the ships and merchants who sold their tobacco and rice in the markets of Europe. As colonial production rose and trade expanded, a business community emerged in the colonies, linking the provinces by lines of trade and identity of interest. With what subject is this passage mainly concerned?

Xem chi tiết 1.1 K lượt xem 5 năm trước

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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter. Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft. On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight. With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality. The word “envisioned” in paragraph 1 is closet in meaning to _____.

Xem chi tiết 508 lượt xem 5 năm trước

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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter. Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft. On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight. With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality. Why is it important that lift be equal on both sides of the helicopter shaft?

Xem chi tiết 530 lượt xem 5 năm trước

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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter. Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft. On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight. With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality. Why was Paul Cornu’s flight important?

Xem chi tiết 1.2 K lượt xem 5 năm trước

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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter. Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft. On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight. With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality. Why was “dissymmetry” important to the early pioneers of helicopter flight?

Xem chi tiết 1.5 K lượt xem 5 năm trước