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Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Diversity is a hallmark of life, an intrinsic feature of living systems in the natural world. The demonstration and celebration of this diversity is an endless rite. Look at the popularity of museums, zoos, aquariums and botanic gardens. The odder the exhibit, the more different it is from the most common and familiar life forms around us, the more successful it is likely to be. Nature does not tire of providing oddities for people who look for them. Biologists have already formally classified 1.7 million species. As many as 30 to 40 million more may remain to be classified. (1) Most people seem to take diversity for granted. If they think about it at all they assume it exists in endless supply. Nevertheless, diversity is endangered as never before in its history. Advocates of perpetual economic growth treat living species as expendable. As a result an extinction crisis of unprecedented magnitude is under way. Worse yet, when diversity needs help most, it is neglected and misunderstood by much of the scientific community that once championed it. (2) Of the two great challenges to the legitimacy of this diversity, the familiar one comes primarily from economists. Their argument, associated with such names as Julian Simon, Malcolm McPherson and the late Herman Kahn, can be paraphrased: "First, if endangered species have a value as resources - which has been greatly exaggerated - then we should be able to quantify that value so that we can make unbiased, objective decisions about which species, if any, we should bother to save, and how much the effort is worth. Secondly, the global threat to the diversity of species, particularly in the tropics, has been overestimated. Thirdly, we have good substitutes for the species and ecosystems that are being lost, and these substitutes will nullify the damage caused by the extinctions". (3) The structure of the argument seems to me to be identical in form to that of an old joke from the American vaudeville circuit. One elderly lady complained to another about her recent vacation at a resort in the Catskill Mountains in New York State. "The food was terrible", she moaned. "Pure poison, I couldn't eat a bite. And the portions were so tiny!" (4) Species may be valuable, but not especially so, and the threat to them has been exaggerated. But this does not matter anyway, say the economists, because we can replace any species that vanishes.(5) It is not clear how much of an impact this argument has on the informed public, but it has certainly provoked an outcry among scientific conservationists. It has set the terms for, and dominated, most of the pro-diversity literature of the past few years, making it a literature of response, thus limiting its scope and creative force. Question 40: Which statement represents the views of economists?
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.         Glass is a remarkable substance made from the simplest raw materials. It can be colored or colorless, monochrome or polychrome, transparent, translucent, or opaque. It is lightweight impermeable to liquids, readily cleaned and reused, durable yet fragile, and often very beautiful. Glass can be decorated in multiple ways and its optical properties are exceptional. In all its myriad forms - as table ware, containers, in architecture and design - glass represents a major achievement in the history of technological developments.         Since the Bronze Age about 3, 000 B.C., glass has been used for making various kinds of objects. It was first made from a mixture of silica, line and an alkali such as soda or potash, and these remained the basic ingredients of glass until the development of lead glass in the seventeenth century. When heated, the mixture becomes soft and malleable and can be formed by various techniques into a vast array of shapes and sizes. The homogeneous mass thus formed by melting then cools to create glass, but in contrast to most materials formed in this way (metals, for instance), glass lacks the crystalline structure normally associated with solids, and instead retains the random molecular structure of a liquid. In effect, as molten glass cools, it progressively stiffens until rigid, but does so without setting up a network of interlocking crystals customarilyassociated with that process. This is why glass shatters so easily when dealt a blow. Why glass deteriorates over time, especially when exposed to moisture, and why glassware must be slowly reheated and uniformly cooled after manufacture to release internal stresses induced by uneven cooling.          Another unusual feature of glass is the manner in which its viscosity changes as it turns from a cold substance into a hot, ductile liquid. Unlike metals that flow or freeze at specific temperatures glass progressively softens as the temperature rises, going through varying stages of malleability until it flows like thick syrup. Each stage of malleability allows the glass to be manipulated into various forms, by different techniques, and if suddenly cooled the object retains the shape achieved at that point. Glass is thus amenable to a greater number of heat-forming techniques than most other materials. Why does the author list the characteristics of glass in paragraph 1?
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Diversity is a hallmark of life, an intrinsic feature of living systems in the natural world. The demonstration and celebration of this diversity is an endless rite. Look at the popularity of museums, zoos, aquariums and botanic gardens. The odder the exhibit, the more different it is from the most common and familiar life forms around us, the more successful it is likely to be. Nature does not tire of providing oddities for people who look for them. Biologists have already formally classified 1.7 million species. As many as 30 to 40 million more may remain to be classified. (1) Most people seem to take diversity for granted. If they think about it at all they assume it exists in endless supply. Nevertheless, diversity is endangered as never before in its history. Advocates of perpetual economic growth treat living species as expendable. As a result an extinction crisis of unprecedented magnitude is under way. Worse yet, when diversity needs help most, it is neglected and misunderstood by much of the scientific community that once championed it. (2) Of the two great challenges to the legitimacy of this diversity, the familiar one comes primarily from economists. Their argument, associated with such names as Julian Simon, Malcolm McPherson and the late Herman Kahn, can be paraphrased: "First, if endangered species have a value as resources - which has been greatly exaggerated - then we should be able to quantify that value so that we can make unbiased, objective decisions about which species, if any, we should bother to save, and how much the effort is worth. Secondly, the global threat to the diversity of species, particularly in the tropics, has been overestimated. Thirdly, we have good substitutes for the species and ecosystems that are being lost, and these substitutes will nullify the damage caused by the extinctions". (3) The structure of the argument seems to me to be identical in form to that of an old joke from the American vaudeville circuit. One elderly lady complained to another about her recent vacation at a resort in the Catskill Mountains in New York State. "The food was terrible", she moaned. "Pure poison, I couldn't eat a bite. And the portions were so tiny!" (4) Species may be valuable, but not especially so, and the threat to them has been exaggerated. But this does not matter anyway, say the economists, because we can replace any species that vanishes.(5) It is not clear how much of an impact this argument has on the informed public, but it has certainly provoked an outcry among scientific conservationists. It has set the terms for, and dominated, most of the pro-diversity literature of the past few years, making it a literature of response, thus limiting its scope and creative force. Question 39: Which adjective best describes the writer's attitude towards the community?
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Diversity is a hallmark of life, an intrinsic feature of living systems in the natural world. The demonstration and celebration of this diversity is an endless rite. Look at the popularity of museums, zoos, aquariums and botanic gardens. The odder the exhibit, the more different it is from the most common and familiar life forms around us, the more successful it is likely to be. Nature does not tire of providing oddities for people who look for them. Biologists have already formally classified 1.7 million species. As many as 30 to 40 million more may remain to be classified. (1) Most people seem to take diversity for granted. If they think about it at all they assume it exists in endless supply. Nevertheless, diversity is endangered as never before in its history. Advocates of perpetual economic growth treat living species as expendable. As a result an extinction crisis of unprecedented magnitude is under way. Worse yet, when diversity needs help most, it is neglected and misunderstood by much of the scientific community that once championed it. (2) Of the two great challenges to the legitimacy of this diversity, the familiar one comes primarily from economists. Their argument, associated with such names as Julian Simon, Malcolm McPherson and the late Herman Kahn, can be paraphrased: "First, if endangered species have a value as resources - which has been greatly exaggerated - then we should be able to quantify that value so that we can make unbiased, objective decisions about which species, if any, we should bother to save, and how much the effort is worth. Secondly, the global threat to the diversity of species, particularly in the tropics, has been overestimated. Thirdly, we have good substitutes for the species and ecosystems that are being lost, and these substitutes will nullify the damage caused by the extinctions". (3) The structure of the argument seems to me to be identical in form to that of an old joke from the American vaudeville circuit. One elderly lady complained to another about her recent vacation at a resort in the Catskill Mountains in New York State. "The food was terrible", she moaned. "Pure poison, I couldn't eat a bite. And the portions were so tiny!" (4) Species may be valuable, but not especially so, and the threat to them has been exaggerated. But this does not matter anyway, say the economists, because we can replace any species that vanishes.(5) It is not clear how much of an impact this argument has on the informed public, but it has certainly provoked an outcry among scientific conservationists. It has set the terms for, and dominated, most of the pro-diversity literature of the past few years, making it a literature of response, thus limiting its scope and creative force. Question 38: Which does the author mean by saying "Most people seem to take diversity for granted"?
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Diversity is a hallmark of life, an intrinsic feature of living systems in the natural world. The demonstration and celebration of this diversity is an endless rite. Look at the popularity of museums, zoos, aquariums and botanic gardens. The odder the exhibit, the more different it is from the most common and familiar life forms around us, the more successful it is likely to be. Nature does not tire of providing oddities for people who look for them. Biologists have already formally classified 1.7 million species. As many as 30 to 40 million more may remain to be classified. (1) Most people seem to take diversity for granted. If they think about it at all they assume it exists in endless supply. Nevertheless, diversity is endangered as never before in its history. Advocates of perpetual economic growth treat living species as expendable. As a result an extinction crisis of unprecedented magnitude is under way. Worse yet, when diversity needs help most, it is neglected and misunderstood by much of the scientific community that once championed it. (2) Of the two great challenges to the legitimacy of this diversity, the familiar one comes primarily from economists. Their argument, associated with such names as Julian Simon, Malcolm McPherson and the late Herman Kahn, can be paraphrased: "First, if endangered species have a value as resources - which has been greatly exaggerated - then we should be able to quantify that value so that we can make unbiased, objective decisions about which species, if any, we should bother to save, and how much the effort is worth. Secondly, the global threat to the diversity of species, particularly in the tropics, has been overestimated. Thirdly, we have good substitutes for the species and ecosystems that are being lost, and these substitutes will nullify the damage caused by the extinctions". (3) The structure of the argument seems to me to be identical in form to that of an old joke from the American vaudeville circuit. One elderly lady complained to another about her recent vacation at a resort in the Catskill Mountains in New York State. "The food was terrible", she moaned. "Pure poison, I couldn't eat a bite. And the portions were so tiny!" (4) Species may be valuable, but not especially so, and the threat to them has been exaggerated. But this does not matter anyway, say the economists, because we can replace any species that vanishes.(5) It is not clear how much of an impact this argument has on the informed public, but it has certainly provoked an outcry among scientific conservationists. It has set the terms for, and dominated, most of the pro-diversity literature of the past few years, making it a literature of response, thus limiting its scope and creative force. Question 37: Which feature of the natural world do people find especially fascinating?
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Diversity is a hallmark of life, an intrinsic feature of living systems in the natural world. The demonstration and celebration of this diversity is an endless rite. Look at the popularity of museums, zoos, aquariums and botanic gardens. The odder the exhibit, the more different it is from the most common and familiar life forms around us, the more successful it is likely to be. Nature does not tire of providing oddities for people who look for them. Biologists have already formally classified 1.7 million species. As many as 30 to 40 million more may remain to be classified. (1) Most people seem to take diversity for granted. If they think about it at all they assume it exists in endless supply. Nevertheless, diversity is endangered as never before in its history. Advocates of perpetual economic growth treat living species as expendable. As a result an extinction crisis of unprecedented magnitude is under way. Worse yet, when diversity needs help most, it is neglected and misunderstood by much of the scientific community that once championed it. (2) Of the two great challenges to the legitimacy of this diversity, the familiar one comes primarily from economists. Their argument, associated with such names as Julian Simon, Malcolm McPherson and the late Herman Kahn, can be paraphrased: "First, if endangered species have a value as resources - which has been greatly exaggerated - then we should be able to quantify that value so that we can make unbiased, objective decisions about which species, if any, we should bother to save, and how much the effort is worth. Secondly, the global threat to the diversity of species, particularly in the tropics, has been overestimated. Thirdly, we have good substitutes for the species and ecosystems that are being lost, and these substitutes will nullify the damage caused by the extinctions". (3) The structure of the argument seems to me to be identical in form to that of an old joke from the American vaudeville circuit. One elderly lady complained to another about her recent vacation at a resort in the Catskill Mountains in New York State. "The food was terrible", she moaned. "Pure poison, I couldn't eat a bite. And the portions were so tiny!" (4) Species may be valuable, but not especially so, and the threat to them has been exaggerated. But this does not matter anyway, say the economists, because we can replace any species that vanishes.(5) It is not clear how much of an impact this argument has on the informed public, but it has certainly provoked an outcry among scientific conservationists. It has set the terms for, and dominated, most of the pro-diversity literature of the past few years, making it a literature of response, thus limiting its scope and creative force. Question 36: The word "intrinsic" in the passage is closest in meaning to _________.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. The word “scores” in paragraph 4 most likely means_________.
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.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. Which of the following notations is most likely to have been included on a musical cue sheet of the early 1900's?
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.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. It maybe inferred from the passage that the first musical cue sheets appeared around
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.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. The word “them” in paragraph 2 refers to__________.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. It can be inferred that orchestra conductors who worked in movie theaters needed to ____.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.         Accustomed though we are to speaking of the films made before 1927 as "silent", the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.         As movie theaters grew in number and importance, a violinist, and perhaps a cellist, would be added to the pianist in certain cases, and in the larger movie theaters small orchestras were formed. For a number of years the selection of music for each film program rested entirely in the hands of the conductor or leader of the orchestra, and very often the principal qualification for holding such a position was not skill or taste so much as the ownership of a large personal library of musical pieces. Since the conductor seldom saw the films until the night before they were to be shown (if, indeed, the conductor was lucky enough to see them then), the musical arrangement was normally improvised in the greatest hurry.         To help meet this difficulty, film distributing companies started the practice of publishing suggestions for musical accompaniments. In 1909, for example, the Edison Company began issuing with their films such indications of mood as “pleasant”, “sad”, “lively”. The suggestions became more explicit, and so emerged the musical cue sheet containing indications of mood, the titles of suitable pieces of music, and precise directions to show where one piece led into the next.         Certain films had music especially composed for them. The most famous of these early special scores was that composed and arranged for D.w. Griffith's film Birth of a Nation, which was released in 1915. The passage mainly discusses music that was_________.
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 35 to 42.    Marianne Moore (1887-1972) once said that her writing could be called poetry only because there was no other name for it. Indeed her poems appear to be extremely compressed essays that happen to be printed in jagged lines on the page. Her subject were varied: animals, laborers, artists, and the craft of poetry. From her general reading came quotations that she found striking or insightful. She included these in her poems, scrupulously enclosed in quotation marks, and sometimes identified in footnotes. Of this practice, she wrote, “Why many quotation marks?’ I am asked ... When a thing has been so well that it could not be said better, why paraphrase it? Hence, my writing is, if not a cabinet of fossils, a kind of collection of flies in amber.” Close observation and concentration on detail and the methods of her poetry.    Marianne Moore grew up in Kirkwood, Missouri, near St. Lois. After graduation from Bryn Mawr College in 1909, she taught commercial subjects at the Indian School in Carlisle, Pennsylvania. Later she became a librarian in New York City. During the 1920’s she was editor of The Dial, an important literary magazine of the period. She lived quietly all her life, mostly in Brooklyn, New York. She spent a lot of time at the Bronx Zoo, fascinated by animals. Her admiration of the Brooklyn Dodgers-before the teammoved to Los Angeles-was widely known. Her first book of poems was published in London in 1921 by a group of friends associated with the Imagist movement. From that time on her poetry has been read with interest by succeeding generations of poets and readers. In 1952 she was awarded the Pulitzer Prize for her Collected Poems. She wrote that she did not write poetry “for money or fame. To eam a living is needful, but it can be done in routine ways. One writes because one has a burning desire to objectify what it is indispensable to one’s happiness to express 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 from 28 to 34.    For more than six million American children, coming home after school means coming back to an empty house. Some deal with the situation by watching TV. Some may hide. But all of them have something in common. They spend part of each day alone. They are called “latchkey children”. They are children who look after themselves while their parents work. And their bad condition has become a subject of concern.    Lynette Long was once the principal of an elementary school. She said, “we had a school rule against wearing jewelry. A lot of kids had chains around their necks with keys attached. I was constantly telling them to put the keys inside shirts. There were so many keys; it never came to my mind what they meant.” Slowly, she learned that they were house keys.    She and her husband began talking to the children who had keys. They learned of the effect working couples and single parents were having on their children. Fear was the biggest problem faced by children at home alone. One in three latchkey children the Longs talked to reported beinu frightened. Many had nightmares and were worried about their own safety    The most common way latchkey children deal with their fears is by hiding. They mav hide in a shower stall, under a bed or in a closet. The second is TV. They often turn the volume up It's hard to get statistics on latchkey children, the Longs have learned. Most parents are slow to admit that they leave their children alone. The phrase “latchkey children” in the passage means children who _____________