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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 answer to each of the questions from 36 to 42The ability to conduct electricity is one of the key properties of a metal. Other solid materials such as silicon can conduct electricity but only effectively at certain temperatures. Also, some substances such as salt (sodium chloride) can conduct when molten or when dissolved in water. The ability of metals to conduct electricity is due to how their atoms bond together. In order to bond together the metal atoms lose at least one of their outermost electrons. This leaves the metal atoms with a positive charge and they are now strictly ions. The lost electrons are free to move in what is known as a sea of electrons. Since the electrons are negatively charged they attract the ions and this is what keeps the structure together. An electric current is a flow of charge and since the electrons in the sea of electrons are free to move they can be made to flow in one direction when a source of electrical energy such as a battery is connected to the metal. Hence we have an electric current flowing through the wire, and this is what makes metals such good conductors of electricity. The only other common solid conducting material that pencil users are likely to encounter is graphite (what the „lead’ of a pencil is made from). Graphite is a form of carbon and again the carbon atoms bond in such a way that there is a sea of electrons that can be made to flow as an electric current. Likewise, if we have an ionic substance like salt we can make the electrically charged ions flow to create a current but only when those ions are free to move, either when the substance is a liquid or dissolved in water. In its solid state an ionic substance like salt cannot conduct electricity as its charged ions cannot flow. Electrical insulators are substances that cannot conduct electricity well either, because they contain no charged particles or any charged particles they might contain do not flow easily. Water itself is a poor conductor of electricity as it does not contain a significant amount of fully charged particles (the ends of a water molecule are partly charged but overall the molecule is neutral). However, most water we encounter does contain dissolved charged particles, so it will be more conductive than pure water. Many of the problems that occur when touching electrical devices with wet hands result from the ever-present salt that is left on our skin through perspiration and it dissolves in the water to make it more conductive. By Helena Gillespie and Rob Gillespie. Science for Primary School Teachers. OUPAccording to the passage, a metal can conduct electricity due to ______.

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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 bestfits each of the numbered blanks from 31 to35.In addition to the challenge to be excellent, American schools have been facing novel problems. They must (31)______ with an influx of immigrant children, many of whom speak little or no English. They must respond to demands that the curriculum reflect the various cultures of all children. Schools must make sure that students develop basic skills for the job market, and they must consider the needs of nontraditional students, such as teenage mothers.Schools are (32)______ these problems in ways that reflect the diversity of the US educational system. They are hiring or training large numbers of teachers of English as a second language and, in some communities, setting up bilingual schools. They are opening up the traditional European-centered curriculum to embrace material from African, Asian, and other cultures. Schools are also teaching cognitive skills to the (33)______ 40 percent of American students who do not go on to higher education. In the (34)______ of a recent report by the Commission on Achieving Necessary Skills, “A strong back, the willingness to work, and a high school diploma were once all that was necessary to (35)______ a start in America. They are no longer. A well- developed mind, a continued willingness to learn and the ability to put knowledge to work are the new keys to the future of our young people, the success of our business, and the economic well-being of the nation.”Điền ô 35

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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 bestfits each of the numbered blanks from 31 to35.In addition to the challenge to be excellent, American schools have been facing novel problems. They must (31)______ with an influx of immigrant children, many of whom speak little or no English. They must respond to demands that the curriculum reflect the various cultures of all children. Schools must make sure that students develop basic skills for the job market, and they must consider the needs of nontraditional students, such as teenage mothers.Schools are (32)______ these problems in ways that reflect the diversity of the US educational system. They are hiring or training large numbers of teachers of English as a second language and, in some communities, setting up bilingual schools. They are opening up the traditional European-centered curriculum to embrace material from African, Asian, and other cultures. Schools are also teaching cognitive skills to the (33)______ 40 percent of American students who do not go on to higher education. In the (34)______ of a recent report by the Commission on Achieving Necessary Skills, “A strong back, the willingness to work, and a high school diploma were once all that was necessary to (35)______ a start in America. They are no longer. A well- developed mind, a continued willingness to learn and the ability to put knowledge to work are the new keys to the future of our young people, the success of our business, and the economic well-being of the nation.”Điền ô 34

Xem chi tiết 304 lượt xem 6 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 bestfits each of the numbered blanks from 31 to35.In addition to the challenge to be excellent, American schools have been facing novel problems. They must (31)______ with an influx of immigrant children, many of whom speak little or no English. They must respond to demands that the curriculum reflect the various cultures of all children. Schools must make sure that students develop basic skills for the job market, and they must consider the needs of nontraditional students, such as teenage mothers.Schools are (32)______ these problems in ways that reflect the diversity of the US educational system. They are hiring or training large numbers of teachers of English as a second language and, in some communities, setting up bilingual schools. They are opening up the traditional European-centered curriculum to embrace material from African, Asian, and other cultures. Schools are also teaching cognitive skills to the (33)______ 40 percent of American students who do not go on to higher education. In the (34)______ of a recent report by the Commission on Achieving Necessary Skills, “A strong back, the willingness to work, and a high school diploma were once all that was necessary to (35)______ a start in America. They are no longer. A well- developed mind, a continued willingness to learn and the ability to put knowledge to work are the new keys to the future of our young people, the success of our business, and the economic well-being of the nation.”Điền ô 33

Xem chi tiết 352 lượt xem 6 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 bestfits each of the numbered blanks from 31 to35.In addition to the challenge to be excellent, American schools have been facing novel problems. They must (31)______ with an influx of immigrant children, many of whom speak little or no English. They must respond to demands that the curriculum reflect the various cultures of all children. Schools must make sure that students develop basic skills for the job market, and they must consider the needs of nontraditional students, such as teenage mothers.Schools are (32)______ these problems in ways that reflect the diversity of the US educational system. They are hiring or training large numbers of teachers of English as a second language and, in some communities, setting up bilingual schools. They are opening up the traditional European-centered curriculum to embrace material from African, Asian, and other cultures. Schools are also teaching cognitive skills to the (33)______ 40 percent of American students who do not go on to higher education. In the (34)______ of a recent report by the Commission on Achieving Necessary Skills, “A strong back, the willingness to work, and a high school diploma were once all that was necessary to (35)______ a start in America. They are no longer. A well- developed mind, a continued willingness to learn and the ability to put knowledge to work are the new keys to the future of our young people, the success of our business, and the economic well-being of the nation.”Điền ô 32

Xem chi tiết 380 lượt xem 6 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 bestfits each of the numbered blanks from 31 to35.In addition to the challenge to be excellent, American schools have been facing novel problems. They must (31)______ with an influx of immigrant children, many of whom speak little or no English. They must respond to demands that the curriculum reflect the various cultures of all children. Schools must make sure that students develop basic skills for the job market, and they must consider the needs of nontraditional students, such as teenage mothers.Schools are (32)______ these problems in ways that reflect the diversity of the US educational system. They are hiring or training large numbers of teachers of English as a second language and, in some communities, setting up bilingual schools. They are opening up the traditional European-centered curriculum to embrace material from African, Asian, and other cultures. Schools are also teaching cognitive skills to the (33)______ 40 percent of American students who do not go on to higher education. In the (34)______ of a recent report by the Commission on Achieving Necessary Skills, “A strong back, the willingness to work, and a high school diploma were once all that was necessary to (35)______ a start in America. They are no longer. A well- developed mind, a continued willingness to learn and the ability to put knowledge to work are the new keys to the future of our young people, the success of our business, and the economic well-being of the nation.”Điền ô 31

Xem chi tiết 309 lượt xem 6 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the best answer to each of the following questions.Shyness may not seem to be a serious complaint, but for some who suffer from it, it can become unbearable. Even talking to a small group of people you know can seem like an ordeal - it can feel as if you’ve been asked to give a speech on a topic you know very little about to a number of experts. You start to feel hot and shaky, your heart beats faster, your knees feel weak, you begin to stutter and the whole experience seems to last forever.The fact of the matter is that shyness is something we often recognize in others: blushing is one of the more visible signs, for example. Yet we do not judge someone harshly because of this. But shyness does mean you are harder to approach, so you become more isolated. As one shy person put it, “It’s like being in a prison, and it’s very hard to break out.”Experts on the subject have come up with various possible solutions, and one has been singled out as being the key to success, namely, finding an interest in common with other people. Spending a lot of time on the sidelines watching other people and envying them because they are much more outgoing doesn’t help; remembering that some of the people you envy most are probably shy themselves. The secret is how you deal with it. And experts have come up with four things you can do today to help. Firstly, you can start by listening to other people. You will find yourself getting interested in what they’re talking about and asking questions, and before you know it, you’ll be having a conversation. Secondly, you could try asking neighbors if you can walk their dog. Like children, pets can be excellent icebreakers for conversations with passers-by. Thirdly, try joining a class to learn something like tap-dancing or flamenco, where people are likely to laugh a lot. You’ll feel relaxed, and also you’ll be much too busy concentrating on what you are doing to feel shy. Lastly, try telling yourself that it doesn’t matter if you say or do something silly. Most people make a fool of themselves every so often, and it’s not the end of the world if you do.How can listening to others prove helpful in combating shyness?

Xem chi tiết 624 lượt xem 6 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the best answer to each of the following questions.Shyness may not seem to be a serious complaint, but for some who suffer from it, it can become unbearable. Even talking to a small group of people you know can seem like an ordeal - it can feel as if you’ve been asked to give a speech on a topic you know very little about to a number of experts. You start to feel hot and shaky, your heart beats faster, your knees feel weak, you begin to stutter and the whole experience seems to last forever.The fact of the matter is that shyness is something we often recognize in others: blushing is one of the more visible signs, for example. Yet we do not judge someone harshly because of this. But shyness does mean you are harder to approach, so you become more isolated. As one shy person put it, “It’s like being in a prison, and it’s very hard to break out.”Experts on the subject have come up with various possible solutions, and one has been singled out as being the key to success, namely, finding an interest in common with other people. Spending a lot of time on the sidelines watching other people and envying them because they are much more outgoing doesn’t help; remembering that some of the people you envy most are probably shy themselves. The secret is how you deal with it. And experts have come up with four things you can do today to help. Firstly, you can start by listening to other people. You will find yourself getting interested in what they’re talking about and asking questions, and before you know it, you’ll be having a conversation. Secondly, you could try asking neighbors if you can walk their dog. Like children, pets can be excellent icebreakers for conversations with passers-by. Thirdly, try joining a class to learn something like tap-dancing or flamenco, where people are likely to laugh a lot. You’ll feel relaxed, and also you’ll be much too busy concentrating on what you are doing to feel shy. Lastly, try telling yourself that it doesn’t matter if you say or do something silly. Most people make a fool of themselves every so often, and it’s not the end of the world if you doWhat do experts believe is the most essential measure to be taken

Xem chi tiết 493 lượt xem 6 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the best answer to each of the following questions.Shyness may not seem to be a serious complaint, but for some who suffer from it, it can become unbearable. Even talking to a small group of people you know can seem like an ordeal - it can feel as if you’ve been asked to give a speech on a topic you know very little about to a number of experts. You start to feel hot and shaky, your heart beats faster, your knees feel weak, you begin to stutter and the whole experience seems to last forever.The fact of the matter is that shyness is something we often recognize in others: blushing is one of the more visible signs, for example. Yet we do not judge someone harshly because of this. But shyness does mean you are harder to approach, so you become more isolated. As one shy person put it, “It’s like being in a prison, and it’s very hard to break out.”Experts on the subject have come up with various possible solutions, and one has been singled out as being the key to success, namely, finding an interest in common with other people. Spending a lot of time on the sidelines watching other people and envying them because they are much more outgoing doesn’t help; remembering that some of the people you envy most are probably shy themselves. The secret is how you deal with it. And experts have come up with four things you can do today to help. Firstly, you can start by listening to other people. You will find yourself getting interested in what they’re talking about and asking questions, and before you know it, you’ll be having a conversation. Secondly, you could try asking neighbors if you can walk their dog. Like children, pets can be excellent icebreakers for conversations with passers-by. Thirdly, try joining a class to learn something like tap-dancing or flamenco, where people are likely to laugh a lot. You’ll feel relaxed, and also you’ll be much too busy concentrating on what you are doing to feel shy. Lastly, try telling yourself that it doesn’t matter if you say or do something silly. Most people make a fool of themselves every so often, and it’s not the end of the world if you doThe word “blushing” in paragraph 2 is closest in meaning to ________.

Xem chi tiết 372 lượt xem 6 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the best answer to each of the following questions.Shyness may not seem to be a serious complaint, but for some who suffer from it, it can become unbearable. Even talking to a small group of people you know can seem like an ordeal - it can feel as if you’ve been asked to give a speech on a topic you know very little about to a number of experts. You start to feel hot and shaky, your heart beats faster, your knees feel weak, you begin to stutter and the whole experience seems to last forever.The fact of the matter is that shyness is something we often recognize in others: blushing is one of the more visible signs, for example. Yet we do not judge someone harshly because of this. But shyness does mean you are harder to approach, so you become more isolated. As one shy person put it, “It’s like being in a prison, and it’s very hard to break out.”Experts on the subject have come up with various possible solutions, and one has been singled out as being the key to success, namely, finding an interest in common with other people. Spending a lot of time on the sidelines watching other people and envying them because they are much more outgoing doesn’t help; remembering that some of the people you envy most are probably shy themselves. The secret is how you deal with it. And experts have come up with four things you can do today to help. Firstly, you can start by listening to other people. You will find yourself getting interested in what they’re talking about and asking questions, and before you know it, you’ll be having a conversation. Secondly, you could try asking neighbors if you can walk their dog. Like children, pets can be excellent icebreakers for conversations with passers-by. Thirdly, try joining a class to learn something like tap-dancing or flamenco, where people are likely to laugh a lot. You’ll feel relaxed, and also you’ll be much too busy concentrating on what you are doing to feel shy. Lastly, try telling yourself that it doesn’t matter if you say or do something silly. Most people make a fool of themselves every so often, and it’s not the end of the world if you doWhy do shy people become more reserved?

Xem chi tiết 0.9 K lượt xem 6 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the best answer to each of the following questions.Shyness may not seem to be a serious complaint, but for some who suffer from it, it can become unbearable. Even talking to a small group of people you know can seem like an ordeal - it can feel as if you’ve been asked to give a speech on a topic you know very little about to a number of experts. You start to feel hot and shaky, your heart beats faster, your knees feel weak, you begin to stutter and the whole experience seems to last forever.The fact of the matter is that shyness is something we often recognize in others: blushing is one of the more visible signs, for example. Yet we do not judge someone harshly because of this. But shyness does mean you are harder to approach, so you become more isolated. As one shy person put it, “It’s like being in a prison, and it’s very hard to break out.”Experts on the subject have come up with various possible solutions, and one has been singled out as being the key to success, namely, finding an interest in common with other people. Spending a lot of time on the sidelines watching other people and envying them because they are much more outgoing doesn’t help; remembering that some of the people you envy most are probably shy themselves. The secret is how you deal with it. And experts have come up with four things you can do today to help. Firstly, you can start by listening to other people. You will find yourself getting interested in what they’re talking about and asking questions, and before you know it, you’ll be having a conversation. Secondly, you could try asking neighbors if you can walk their dog. Like children, pets can be excellent icebreakers for conversations with passers-by. Thirdly, try joining a class to learn something like tap-dancing or flamenco, where people are likely to laugh a lot. You’ll feel relaxed, and also you’ll be much too busy concentrating on what you are doing to feel shy. Lastly, try telling yourself that it doesn’t matter if you say or do something silly. Most people make a fool of themselves every so often, and it’s not the end of the world if you do.

Xem chi tiết 1 K lượt xem 6 năm trước