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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 for each of the questionsHumans 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.With what topic does this passage primarily deal?

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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.Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly. To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.In the author's judgment _______ 

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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.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. Who would be MOST likely to use Morse code?

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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.Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.The word “disparage” in the passage mostly means _______ 

Xem chi tiết 354 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 answer to each of the questions.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. Sign language is said to be very picturesque and exact and can be used internationally EXCEPT for

Xem chi tiết 399 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 answer to each of the questions.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. The word "wink" in paragraph 2 means most nearly the same as

Xem chi tiết 816 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 answer to each of the questions.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. How many different forms of communication are mentioned here?

Xem chi tiết 378 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 answer to each of the questions.Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show why speech is primary and writing secondary to language. Human beings have been writing at least 5,000 years, but they have been talking for much longer, doubtless ever since there have been human beings. When writing developed, it was derived from and represented speech, although imperfectly. Even today, there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any child who is not severely handicapped physically or mentally will learn to talk: a normal man cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write; in the past, many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write while some who learn the rudiments of those skills do so imperfectly.To affirm the primacy of speech over writing is not to disparage the later. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.The word “acquire” in the passage mostly means _______ 

Xem chi tiết 573 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 answer to each of the questions.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. Which form other than oral speech would be most commonly used among blind people?

Xem chi tiết 781 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 answer to each of the questions.It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50-kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them. These fractured columns send out distinctive vibration pattems. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.The word “parched” in paragraph 1 is closest in meaning to  _________ .

Xem chi tiết 494 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 answer to each of the questions.Ever since humans inhabited the earth, they have made use of various forms of communication. Generally, this expression of thoughts and feelings has been in the form of oral speech. When there is a language barrier, communication is accomplished through sign language in which motions stand for letters, words, and ideas. Tourists, the deaf, and the mute have had to resort to this form of expression. Many of these symbols of whole words are very picturesque and exact and can be used internationally; spelling, however, cannot.Body language transmits ideas or thoughts by certain actions, either intentionally or unintentionally. A wink can be a way of flirting or indicating that the party is only joking. A nod signifies approval, while shaking the head indicates a negative reaction.Other forms of nonlinguistic language can be found in Braille (a system of raised dots read with the fingertips), signal flags, Morse code, and smoke signals. Road maps and picture signs also guide, warn, and instruct people.While verbalization is the most common form of language, other systems and techniques also express human thoughts and feelings. All of the following statements are true EXCEPT

Xem chi tiết 870 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 answer to each of the questions.It’s a sound you will probably never hear, a sickened tree sending out a distress signal. But a group of scientists has heard the cries, and they think some insects also hear the trees and are drawn to them like vulture to a dying animal. Researchers with the US Department of Agriculture’s Forest Service fastened sensors to the bark of drought-stricken trees clearly heard distress calls. According to one of the scientists, most parched trees transmit their plight in the 50-hertz to 50-kilohertz range. (The unaided human ear can detect no more than 20 kilohertz). Red oak, maple, white pine, and birch all make slightly different sounds in the form of vibrations at the surface of the wood.The scientists think that the vibrations are created when the water columns inside tubes that run along the length of the tree break, a result of too little water following through them. These fractured columns send out distinctive vibration pattems. Because some insects communicate at ultrasonic frequencies, they may pick up the trees' vibration and attack the weakened trees. Researchers are now running tests with potted trees that have been deprived of water to see if the sound is what attracts the insects. “Water-stressed trees also smell differently from other trees, and they experience thermal changes, so insects could be responding to something other than sound”, one scientist said.It can be inferred from the passage that the sounds produced by the trees ________ .

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