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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 42Most parents want their sons and daughters to have equal chances of success when they grow up. Today, equality of the sexes is largely mandated by public policy and law. However, old- fashioned ideas and a lot of prejudice are still part of our culture and present challenging questions for parents.Gender stereotypes are rigid ideas about how boys and girls should behave. We all know what these stereotypes are: A "feminine" girls should be insecure, accommodating and a little illogical   in her thinking. A "masculine" boy should be strong, unemotional, aggressive, and competitive.  How are children exposed to these stereotypes? According to the researchers David and Myra Sadker of the American University of Washington, D.C., boys and girls are often treated differently in the classroom. They found out that when boys speak, teachers usually offer constructive comments, when girls speech, teachers tend to focus on the behavior. It's more important how the girls act rather than what they say.The emphasis on differences begins at birth and continues throughout childhood. For example, few people would give pink baby's clothes to a boy or a blue blanket to a girl. Later, many of us give girls dolls and miniature kitchenware, while boys receive action figures and construction sets. There's nothing wrong with that. The problem arises when certain activities are deemed appropriate for one sex but not the other. According to Heather J. Nicholson, Ph.D., director of the National Resource Center for Girls, Inc., this kind of practice prevents boys and girls from acquiring important skills for their future lives."The fact is," says Nicholson, "that society functions as a kind of sorting machine regarding gender. In a recent survey, fifty-eight percent of eighth-grade girls but only six percent of boys earned money caring for younger children. On the other hand, twenty-seven percent of boys but only three percent of girls earned money doing lawn work". If we are serious about educating a generation to be good workers and parents, we need to eliminate such stereotypes as those mentioned previously.Gender stereotypes inevitably are passed to our children. However, by becoming aware of the messages our children receive, we can help them develop ways to overcome these incorrect ideas. To counteract these ideas, parents can look for ways to challenge and support their children, and to encourage confidence in ways that go beyond what society's fixed ideas about differences of sext are.(Source: https://en.isicollective.com)According to the second passage, David and Myra Sadker of the American University of Washington, D.0 found that_____.

Xem chi tiết 598 lượt xem 4 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 36 to 42Most parents want their sons and daughters to have equal chances of success when they grow up. Today, equality of the sexes is largely mandated by public policy and law. However, old- fashioned ideas and a lot of prejudice are still part of our culture and present challenging questions for parents.Gender stereotypes are rigid ideas about how boys and girls should behave. We all know what these stereotypes are: A "feminine" girls should be insecure, accommodating and a little illogical   in her thinking. A "masculine" boy should be strong, unemotional, aggressive, and competitive.  How are children exposed to these stereotypes? According to the researchers David and Myra Sadker of the American University of Washington, D.C., boys and girls are often treated differently in the classroom. They found out that when boys speak, teachers usually offer constructive comments, when girls speech, teachers tend to focus on the behavior. It's more important how the girls act rather than what they say.The emphasis on differences begins at birth and continues throughout childhood. For example, few people would give pink baby's clothes to a boy or a blue blanket to a girl. Later, many of us give girls dolls and miniature kitchenware, while boys receive action figures and construction sets. There's nothing wrong with that. The problem arises when certain activities are deemed appropriate for one sex but not the other. According to Heather J. Nicholson, Ph.D., director of the National Resource Center for Girls, Inc., this kind of practice prevents boys and girls from acquiring important skills for their future lives."The fact is," says Nicholson, "that society functions as a kind of sorting machine regarding gender. In a recent survey, fifty-eight percent of eighth-grade girls but only six percent of boys earned money caring for younger children. On the other hand, twenty-seven percent of boys but only three percent of girls earned money doing lawn work". If we are serious about educating a generation to be good workers and parents, we need to eliminate such stereotypes as those mentioned previously.Gender stereotypes inevitably are passed to our children. However, by becoming aware of the messages our children receive, we can help them develop ways to overcome these incorrect ideas. To counteract these ideas, parents can look for ways to challenge and support their children, and to encourage confidence in ways that go beyond what society's fixed ideas about differences of sext are.(Source: https://en.isicollective.com)The word "deemed" in paragraph 3 is closest in meaning to ___.

Xem chi tiết 666 lượt xem 4 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 36 to 42Most parents want their sons and daughters to have equal chances of success when they grow up. Today, equality of the sexes is largely mandated by public policy and law. However, old- fashioned ideas and a lot of prejudice are still part of our culture and present challenging questions for parents.Gender stereotypes are rigid ideas about how boys and girls should behave. We all know what these stereotypes are: A "feminine" girls should be insecure, accommodating and a little illogical   in her thinking. A "masculine" boy should be strong, unemotional, aggressive, and competitive.  How are children exposed to these stereotypes? According to the researchers David and Myra Sadker of the American University of Washington, D.C., boys and girls are often treated differently in the classroom. They found out that when boys speak, teachers usually offer constructive comments, when girls speech, teachers tend to focus on the behavior. It's more important how the girls act rather than what they say.The emphasis on differences begins at birth and continues throughout childhood. For example, few people would give pink baby's clothes to a boy or a blue blanket to a girl. Later, many of us give girls dolls and miniature kitchenware, while boys receive action figures and construction sets. There's nothing wrong with that. The problem arises when certain activities are deemed appropriate for one sex but not the other. According to Heather J. Nicholson, Ph.D., director of the National Resource Center for Girls, Inc., this kind of practice prevents boys and girls from acquiring important skills for their future lives."The fact is," says Nicholson, "that society functions as a kind of sorting machine regarding gender. In a recent survey, fifty-eight percent of eighth-grade girls but only six percent of boys earned money caring for younger children. On the other hand, twenty-seven percent of boys but only three percent of girls earned money doing lawn work". If we are serious about educating a generation to be good workers and parents, we need to eliminate such stereotypes as those mentioned previously.Gender stereotypes inevitably are passed to our children. However, by becoming aware of the messages our children receive, we can help them develop ways to overcome these incorrect ideas. To counteract these ideas, parents can look for ways to challenge and support their children, and to encourage confidence in ways that go beyond what society's fixed ideas about differences of sext are.(Source: https://en.isicollective.com)Which of the following could be the main idea of the passage?

Xem chi tiết 2.9 K lượt xem 4 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 31 to 35Deep brain stimulation (DBS), an experimental technology that involves implanting a pacemaker-like device in a patient’s brain to send electrical impulses, is a hotly debated subject in the field of medicine. It is an inherently risky procedure and the exact effects on the human brain aren’t yet fully understood.But some practitioners believe it could be a way to alleviate the symptoms of depression or even help treat Alzheimer’s — and now they suspect it could help with drug addiction as well. In a world’s first, according to the Associated Press, a patient in Shanghai’s Ruijin Hospital had a DBS device implanted in his brain to treat his addiction to methamphetamine. And the device has had an astonishingly positive effect, the patient says. “This machine is pretty magical. He adjusts it to make you happy and you’re happy, to make you nervous and you’re nervous,” he told the Associated Press. “It controls your happiness, anger, grief and joy.”Other studies in China have yielded mixed results trying to treat opioid addictions using DBS, according to the AP. In the United States, at least two studies that tried to treat alcoholism with DBS were dropped for not being able to justify the risks. The idea of using DBS to treat drug addiction has raised concerns in medical communities across the globe about brain hemorrhage, seizures, or personality changesAll of the following are mentioned in the passage as concerns about the use of DBS to treat drug addiction in medical communities worldwide EXCEPT______________

Xem chi tiết 2 K lượt xem 4 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 31 to 35Deep brain stimulation (DBS), an experimental technology that involves implanting a pacemaker-like device in a patient’s brain to send electrical impulses, is a hotly debated subject in the field of medicine. It is an inherently risky procedure and the exact effects on the human brain aren’t yet fully understood.But some practitioners believe it could be a way to alleviate the symptoms of depression or even help treat Alzheimer’s — and now they suspect it could help with drug addiction as well. In a world’s first, according to the Associated Press, a patient in Shanghai’s Ruijin Hospital had a DBS device implanted in his brain to treat his addiction to methamphetamine. And the device has had an astonishingly positive effect, the patient says. “This machine is pretty magical. He adjusts it to make you happy and you’re happy, to make you nervous and you’re nervous,” he told the Associated Press. “It controls your happiness, anger, grief and joy.”Other studies in China have yielded mixed results trying to treat opioid addictions using DBS, according to the AP. In the United States, at least two studies that tried to treat alcoholism with DBS were dropped for not being able to justify the risks. The idea of using DBS to treat drug addiction has raised concerns in medical communities across the globe about brain hemorrhage, seizures, or personality changesAccording to the passage, the use of DBS_____________

Xem chi tiết 3.5 K lượt xem 4 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 31 to 35Deep brain stimulation (DBS), an experimental technology that involves implanting a pacemaker-like device in a patient’s brain to send electrical impulses, is a hotly debated subject in the field of medicine. It is an inherently risky procedure and the exact effects on the human brain aren’t yet fully understood.But some practitioners believe it could be a way to alleviate the symptoms of depression or even help treat Alzheimer’s — and now they suspect it could help with drug addiction as well. In a world’s first, according to the Associated Press, a patient in Shanghai’s Ruijin Hospital had a DBS device implanted in his brain to treat his addiction to methamphetamine. And the device has had an astonishingly positive effect, the patient says. “This machine is pretty magical. He adjusts it to make you happy and you’re happy, to make you nervous and you’re nervous,” he told the Associated Press. “It controls your happiness, anger, grief and joy.”Other studies in China have yielded mixed results trying to treat opioid addictions using DBS, according to the AP. In the United States, at least two studies that tried to treat alcoholism with DBS were dropped for not being able to justify the risks. The idea of using DBS to treat drug addiction has raised concerns in medical communities across the globe about brain hemorrhage, seizures, or personality changesThe word “It” in paragraph 3 refers to__________________

Xem chi tiết 2.5 K lượt xem 4 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 31 to 35Deep brain stimulation (DBS), an experimental technology that involves implanting a pacemaker-like device in a patient’s brain to send electrical impulses, is a hotly debated subject in the field of medicine. It is an inherently risky procedure and the exact effects on the human brain aren’t yet fully understood.But some practitioners believe it could be a way to alleviate the symptoms of depression or even help treat Alzheimer’s — and now they suspect it could help with drug addiction as well. In a world’s first, according to the Associated Press, a patient in Shanghai’s Ruijin Hospital had a DBS device implanted in his brain to treat his addiction to methamphetamine. And the device has had an astonishingly positive effect, the patient says. “This machine is pretty magical. He adjusts it to make you happy and you’re happy, to make you nervous and you’re nervous,” he told the Associated Press. “It controls your happiness, anger, grief and joy.”Other studies in China have yielded mixed results trying to treat opioid addictions using DBS, according to the AP. In the United States, at least two studies that tried to treat alcoholism with DBS were dropped for not being able to justify the risks. The idea of using DBS to treat drug addiction has raised concerns in medical communities across the globe about brain hemorrhage, seizures, or personality changesThe word “alleviate” in paragraph 2 is closest in meaning to_____

Xem chi tiết 3.5 K lượt xem 4 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 31 to 35Deep brain stimulation (DBS), an experimental technology that involves implanting a pacemaker-like device in a patient’s brain to send electrical impulses, is a hotly debated subject in the field of medicine. It is an inherently risky procedure and the exact effects on the human brain aren’t yet fully understood.But some practitioners believe it could be a way to alleviate the symptoms of depression or even help treat Alzheimer’s — and now they suspect it could help with drug addiction as well. In a world’s first, according to the Associated Press, a patient in Shanghai’s Ruijin Hospital had a DBS device implanted in his brain to treat his addiction to methamphetamine. And the device has had an astonishingly positive effect, the patient says. “This machine is pretty magical. He adjusts it to make you happy and you’re happy, to make you nervous and you’re nervous,” he told the Associated Press. “It controls your happiness, anger, grief and joy.”Other studies in China have yielded mixed results trying to treat opioid addictions using DBS, according to the AP. In the United States, at least two studies that tried to treat alcoholism with DBS were dropped for not being able to justify the risks. The idea of using DBS to treat drug addiction has raised concerns in medical communities across the globe about brain hemorrhage, seizures, or personality changesWhat is the passage mainly about?

Xem chi tiết 1.9 K lượt xem 4 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 26 to 30Mobile phones: a benefit or social nuisance?         Few people under 30 will be able to imagine a time before the existence of mobile phones. Neither will they be (26)_________of the harmful effect that many people predicted text language would have on young people’s language skills.          Interestingly, linguists nowadays believe that expressing oneself clearly in texts is evidence of a good background in grammar and sentence structure. Mobile phones are credited with encouraging people to communicate more. They can also provide reassurance to people (27)_________are alone in dangerous situations. Some people use mobile phones as a kind of barrier to unwelcome social contact; texting can signal your unavailability to (28)_________people in the same way that wearing sunglasses and headphones does.          Some issues with mobile phones are still controversial. Talking loudly on the phone while on public transport is thought to be rude and (29)_________by many people in the UK. (30)_________, a significant minority of people still do it, despite the sighing and other obvious signs of disapproval from their fellow passengers.(Adapted from “AdvancedExpert’’ by Jan Bell and Roger Gower)Điền vào ô 30

Xem chi tiết 2.4 K lượt xem 4 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 26 to 30Mobile phones: a benefit or social nuisance?         Few people under 30 will be able to imagine a time before the existence of mobile phones. Neither will they be (26)_________of the harmful effect that many people predicted text language would have on young people’s language skills.          Interestingly, linguists nowadays believe that expressing oneself clearly in texts is evidence of a good background in grammar and sentence structure. Mobile phones are credited with encouraging people to communicate more. They can also provide reassurance to people (27)_________are alone in dangerous situations. Some people use mobile phones as a kind of barrier to unwelcome social contact; texting can signal your unavailability to (28)_________people in the same way that wearing sunglasses and headphones does.          Some issues with mobile phones are still controversial. Talking loudly on the phone while on public transport is thought to be rude and (29)_________by many people in the UK. (30)_________, a significant minority of people still do it, despite the sighing and other obvious signs of disapproval from their fellow passengers.(Adapted from “AdvancedExpert’’ by Jan Bell and Roger Gower)Điền vào ô 29

Xem chi tiết 4.5 K lượt xem 4 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 26 to 30Mobile phones: a benefit or social nuisance?         Few people under 30 will be able to imagine a time before the existence of mobile phones. Neither will they be (26)_________of the harmful effect that many people predicted text language would have on young people’s language skills.          Interestingly, linguists nowadays believe that expressing oneself clearly in texts is evidence of a good background in grammar and sentence structure. Mobile phones are credited with encouraging people to communicate more. They can also provide reassurance to people (27)_________are alone in dangerous situations. Some people use mobile phones as a kind of barrier to unwelcome social contact; texting can signal your unavailability to (28)_________people in the same way that wearing sunglasses and headphones does.          Some issues with mobile phones are still controversial. Talking loudly on the phone while on public transport is thought to be rude and (29)_________by many people in the UK. (30)_________, a significant minority of people still do it, despite the sighing and other obvious signs of disapproval from their fellow passengers.(Adapted from “AdvancedExpert’’ by Jan Bell and Roger Gower)Điền vào ô 28

Xem chi tiết 797 lượt xem 4 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 26 to 30Mobile phones: a benefit or social nuisance?         Few people under 30 will be able to imagine a time before the existence of mobile phones. Neither will they be (26)_________of the harmful effect that many people predicted text language would have on young people’s language skills.          Interestingly, linguists nowadays believe that expressing oneself clearly in texts is evidence of a good background in grammar and sentence structure. Mobile phones are credited with encouraging people to communicate more. They can also provide reassurance to people (27)_________are alone in dangerous situations. Some people use mobile phones as a kind of barrier to unwelcome social contact; texting can signal your unavailability to (28)_________people in the same way that wearing sunglasses and headphones does.          Some issues with mobile phones are still controversial. Talking loudly on the phone while on public transport is thought to be rude and (29)_________by many people in the UK. (30)_________, a significant minority of people still do it, despite the sighing and other obvious signs of disapproval from their fellow passengers.(Adapted from “AdvancedExpert’’ by Jan Bell and Roger Gower)Điền vào ô 27

Xem chi tiết 1.3 K lượt xem 4 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 26 to 30Mobile phones: a benefit or social nuisance?         Few people under 30 will be able to imagine a time before the existence of mobile phones. Neither will they be (26)_________of the harmful effect that many people predicted text language would have on young people’s language skills.          Interestingly, linguists nowadays believe that expressing oneself clearly in texts is evidence of a good background in grammar and sentence structure. Mobile phones are credited with encouraging people to communicate more. They can also provide reassurance to people (27)_________are alone in dangerous situations. Some people use mobile phones as a kind of barrier to unwelcome social contact; texting can signal your unavailability to (28)_________people in the same way that wearing sunglasses and headphones does.          Some issues with mobile phones are still controversial. Talking loudly on the phone while on public transport is thought to be rude and (29)_________by many people in the UK. (30)_________, a significant minority of people still do it, despite the sighing and other obvious signs of disapproval from their fellow passengers.(Adapted from “AdvancedExpert’’ by Jan Bell and Roger Gower)Điền vào ô 26

Xem chi tiết 3.7 K lượt xem 4 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 36 to 42.There are two basic types of glaciers, those that flow outward in all directions with little regard for any underlying terrain and those that are confined by terrain to a particular path.The first category of glaciers includes those massive blankets that cover whole continents, appropriately called ice sheets. There must be over 50,000 square kilometers of land covered with ice for the glacier to qualify as an ice sheet, when portions of an ice sheet spread out over the ocean, they form ice shelves.About 20,000 years ago the Cordilleran Ice sheet covered nearly all the mountains in southern Alaska, western Canada, and the western United States. It was about 3 kilometers deep at its thickest point in northern Alberta. Now there are only two sheets left on Earth, those covering Greenland and Antarctica.Any domelike body of ice that also flows out in all directions but covers less than 50,000 square kilometers is called an ice cap. Although ice caps are rare nowadays, there are a number in northeastern Canada, on Baffin Island, and on the Queen Elizabeth Islands.The second category of glaciers includes those of a variety of shapes and sizes generally called mountain or alpine glaciers. Mountain glaciers are typically identified by the landform that controls their flow. One form of mountain glacier that resembles an ice cap in that it flows outward in several directions is called an ice field. The difference between an ice field and an ice cap is subtle. Essentially, the flow of an ice field is somewhat controlled by surrounding terrain and thus does not have the domelike shape of a cap. There are several ice fields in the Wrangell. St. Elias, and Chugach mountains of Alaska and northern British Columbia.Less spectacular than large ice fields are the most common types of mountain glaciers: the cirque and valley glaciers. Cirque glaciers are found in depressions in the surface of the land and have a characteristic circular shape. The ice of valley glaciers, bound by terrain, flows down valleys, curves around their corners, and falls over cliffs.All of the following are alpine glaciers EXCEPT_______

Xem chi tiết 675 lượt xem 4 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 36 to 42.There are two basic types of glaciers, those that flow outward in all directions with little regard for any underlying terrain and those that are confined by terrain to a particular path.The first category of glaciers includes those massive blankets that cover whole continents, appropriately called ice sheets. There must be over 50,000 square kilometers of land covered with ice for the glacier to qualify as an ice sheet, when portions of an ice sheet spread out over the ocean, they form ice shelves.About 20,000 years ago the Cordilleran Ice sheet covered nearly all the mountains in southern Alaska, western Canada, and the western United States. It was about 3 kilometers deep at its thickest point in northern Alberta. Now there are only two sheets left on Earth, those covering Greenland and Antarctica.Any domelike body of ice that also flows out in all directions but covers less than 50,000 square kilometers is called an ice cap. Although ice caps are rare nowadays, there are a number in northeastern Canada, on Baffin Island, and on the Queen Elizabeth Islands.The second category of glaciers includes those of a variety of shapes and sizes generally called mountain or alpine glaciers. Mountain glaciers are typically identified by the landform that controls their flow. One form of mountain glacier that resembles an ice cap in that it flows outward in several directions is called an ice field. The difference between an ice field and an ice cap is subtle. Essentially, the flow of an ice field is somewhat controlled by surrounding terrain and thus does not have the domelike shape of a cap. There are several ice fields in the Wrangell. St. Elias, and Chugach mountains of Alaska and northern British Columbia.Less spectacular than large ice fields are the most common types of mountain glaciers: the cirque and valley glaciers. Cirque glaciers are found in depressions in the surface of the land and have a characteristic circular shape. The ice of valley glaciers, bound by terrain, flows down valleys, curves around their corners, and falls over cliffs.The word “their” in last paragraph refers to__________

Xem chi tiết 2.9 K lượt xem 4 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 36 to 42.There are two basic types of glaciers, those that flow outward in all directions with little regard for any underlying terrain and those that are confined by terrain to a particular path.The first category of glaciers includes those massive blankets that cover whole continents, appropriately called ice sheets. There must be over 50,000 square kilometers of land covered with ice for the glacier to qualify as an ice sheet, when portions of an ice sheet spread out over the ocean, they form ice shelves.About 20,000 years ago the Cordilleran Ice sheet covered nearly all the mountains in southern Alaska, western Canada, and the western United States. It was about 3 kilometers deep at its thickest point in northern Alberta. Now there are only two sheets left on Earth, those covering Greenland and Antarctica.Any domelike body of ice that also flows out in all directions but covers less than 50,000 square kilometers is called an ice cap. Although ice caps are rare nowadays, there are a number in northeastern Canada, on Baffin Island, and on the Queen Elizabeth Islands.The second category of glaciers includes those of a variety of shapes and sizes generally called mountain or alpine glaciers. Mountain glaciers are typically identified by the landform that controls their flow. One form of mountain glacier that resembles an ice cap in that it flows outward in several directions is called an ice field. The difference between an ice field and an ice cap is subtle. Essentially, the flow of an ice field is somewhat controlled by surrounding terrain and thus does not have the domelike shape of a cap. There are several ice fields in the Wrangell. St. Elias, and Chugach mountains of Alaska and northern British Columbia.Less spectacular than large ice fields are the most common types of mountain glaciers: the cirque and valley glaciers. Cirque glaciers are found in depressions in the surface of the land and have a characteristic circular shape. The ice of valley glaciers, bound by terrain, flows down valleys, curves around their corners, and falls over cliffs.The word “subtle” in paragraph 5 could best be replaced by____________

Xem chi tiết 525 lượt xem 4 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 36 to 42.There are two basic types of glaciers, those that flow outward in all directions with little regard for any underlying terrain and those that are confined by terrain to a particular path.The first category of glaciers includes those massive blankets that cover whole continents, appropriately called ice sheets. There must be over 50,000 square kilometers of land covered with ice for the glacier to qualify as an ice sheet, when portions of an ice sheet spread out over the ocean, they form ice shelves.About 20,000 years ago the Cordilleran Ice sheet covered nearly all the mountains in southern Alaska, western Canada, and the western United States. It was about 3 kilometers deep at its thickest point in northern Alberta. Now there are only two sheets left on Earth, those covering Greenland and Antarctica.Any domelike body of ice that also flows out in all directions but covers less than 50,000 square kilometers is called an ice cap. Although ice caps are rare nowadays, there are a number in northeastern Canada, on Baffin Island, and on the Queen Elizabeth Islands.The second category of glaciers includes those of a variety of shapes and sizes generally called mountain or alpine glaciers. Mountain glaciers are typically identified by the landform that controls their flow. One form of mountain glacier that resembles an ice cap in that it flows outward in several directions is called an ice field. The difference between an ice field and an ice cap is subtle. Essentially, the flow of an ice field is somewhat controlled by surrounding terrain and thus does not have the domelike shape of a cap. There are several ice fields in the Wrangell. St. Elias, and Chugach mountains of Alaska and northern British Columbia.Less spectacular than large ice fields are the most common types of mountain glaciers: the cirque and valley glaciers. Cirque glaciers are found in depressions in the surface of the land and have a characteristic circular shape. The ice of valley glaciers, bound by terrain, flows down valleys, curves around their corners, and falls over cliffs.According to the passage, where was the Cordilleran Ice Sheet thickest?

Xem chi tiết 838 lượt xem 4 năm trước