Danh sách câu hỏi:

Câu 1:

Choose a word in each line that has different stress pattern

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Câu 8:

Choose the best answer for each of the following sentences
………, no one was absent from the farewell party last night

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Câu 16:

Choose the best answer for each of the following sentences
We need to import……..from abroad.

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Câu 20:

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is CLOSEST in meaning to each of the following questions
I’m sure Luisa was very disappointed when she failed the exam

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Câu 21:

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is CLOSEST in meaning to each of the following questions
“You had better see a doctor if the sore throat does not clear up.” she said to me.

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Câu 22:

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is CLOSEST in meaning to each of the following questions
Without her teacher’s advice, she would never have written such a good essay

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Câu 23:

Mark the letter A, B, C, or D on you answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
She tried very hard to pass the driving test. She could hardly pass it.

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Câu 24:

Mark the letter A, B, C, or D on you answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
Mary loved her stuffed animal when she was young. She couldn’t sleep without it.

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Câu 25:

Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges.
- "Excuse me. Where‟s the parking lot?" - “…………”

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Câu 31:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:Which of the following is not true about India‟s caste system?

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Câu 32:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:The word “this” in paragraph 1 refers to ________.

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Câu 33:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:What is the caste system mainly based on?

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Câu 34:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving. 
Question:
What kind of job would a Brahmin likely have?

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Câu 35:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:What could replace the word “ruling” in paragraph 3?

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Câu 36:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:All of the following are true about the Harijan EXCEPT that ________.

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Câu 37:

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

Understanding India's Caste System

It has been said that life is what we make of it. In other words, if we work hard and focus on our goals, we can have great careers and enjoy high status is society. However, these opportunities don‟t exist for everyone. In some places, the family you are born into will decide almost everything about your life. India‟s caste system is an example of this.

The caste system is a major part of the Hindu religion that has existed for thousands of years. It is a way of organizing and grouping people based on the occupation of the family. Castes will determine whom people can socialize with and their place in society. Originally, a person‟s caste was supposed to be determined by their personality, but over time it has been linked to their job and family.

There are four classes, also known as varnas, in India‟s caste system. The highest one is Brahmin. People in this class have jobs in education and religion. These are seen as extremely important functions for the society as they deal with the knowledge. The second highest level is the Kshatriya, or ruling class. People from this group can be soldiers, landowners, or have jobs in politics. The class beneath this is the Vaishya. These people often work in the commercial sector as merchants. The fourth class level is the Shudra. Shudras typically work as unskilled labourers doing factory or farm work, or they may also be employed as artists.

There is another group, the Harijan, that is at the bottom and considered to be outside of the caste system. For many years, they were known as Untouchables, people from this caste held the most undesirable jobs in society, such as cleaning up garbage. Furthermore, they weren‟t allowed to pray at public temples or drink water from the same wells as other classes. If someone from another caste came into contact with an Untouchable, they were considered dirty and would be expected to bathe vigorously to clean themselves.

Although the caste system still exists in India, the government is taking steps to improve the living conditions and decrease unemployment rates for the Shudras and Harijan. This includes providing better health care, offering literacy programmes, and making sure that people from higher social classes do not exploit them. It seems unlikely that the caste system will disappear any time soon, but the overall conditions for those at the bottom do seem to be improving.

Question:What does the passage suggest about the future of the caste system?

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Câu 43:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:With what topic does this passage primarily deal?

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Câu 44:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:The word ‘marring’ in bold is closest in meaning to

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Câu 45:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:The word ‘clog’ in bold is closest in meaning to

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Câu 46:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:Which of the following terms does the author define in the first paragraph?

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Câu 47:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season. 
Question:
Which of the following statements about the use of chemical agents as herbicides would the author most likely agree?

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Câu 48:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:The word ‘innate’ in bold is closest in meaning to

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Câu 49:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:The word ‘applications’ in bold could best be replaced by which of the following?

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Câu 50:

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

Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds – any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.

The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.

In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world‟s weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.

The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.

Question:Which of the following best describes the organization of the passage?

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