Câu hỏi:
31/10/2020 368Read the following passage and mark the letter A, B, tr or I) to indicate the correct answer to each of the questions from 36 to 42.
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 fanning. 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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Trả lời:
Giải bởi Vietjack
Đáp án D
A. Tầm quan trọng của nền công nghiệp hóa chất.
B. Sự nguy hiểm của chất hóa học độc hại
C. Yêu cầu cấm sử dụng thuốc diệt cỏ
D. Lợi ích của việc sử dụng tác nhân sinh học so với tác nhân hóa học.
Giải thích: Đoạn 1 nói về ảnh hưởng xấu của cỏ dại, đoạn 2 nói về chất hóa học tác động xấu, đoạn 3 chuyển ý và đoạn 4 nói về mặt tốt của tác nhân sinh học. Như vậy nhìn lại toàn bộ thì mục đích chính là so sánh để làm nôi bật lợi ích của việc dùng tác nhân sinh học.
Nhà sách VIETJACK:
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 1:
By the age of ten, Helen ______ Braille as well as the manual alphabet and even learned to use the typewriter.
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Câu 2:
He suddenly saw Sue ______ the room. He pushed his way _______the crowd of people to get to her.
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Câu 3:
Mark the letter A, B, C or D to indicate the most suitable response to complete each of the following exchanges.
: _______ make a phone call here? B: Sure. Go ahead.
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Câu 4:
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.
Let children learn to judge their own work. A child learning to talk does not learn by being corrected all the time. If corrected too much, he will stop talking. He notices a thousand times a day the difference between the language he uses and the language those around him use. Bit by bit, he makes the necessary changes to make his language like other people's. In the same way, children learn all the other things they learn to do without being taught - to talk, run, climb, whistle, ride a bicycle - compare their own performances with those of more skilled people, and slowly make the needed changes. But in school we never give a child a chance to find out his mistakes for himself, let alone correct them. We do it all for him. We act as if we thought that he would never notice a mistake unless it was pointed out to him, or correct it unless he was made to. Soon he becomes dependent on the teacher. Let him do it himself. Let him work out, with the help of other children if he wants it, what this word says, what the answer is to that problem, whether this is a good way of saying or doing this or not.
If it is a matter of right answers, as it may be in mathematics or science, give him the answer book. Let him correct his own papers. Why should we teachers waste time on such routine work? Our job should be to help the child when he tells us that he can't find the way to get the right answer. Let's end all this nonsense of grades, exams, and marks. Let us throw them all out, and let the children learn what all educated persons must someday learn, how to measure their own understanding, how to know what they know or do not know.
Let them get on with this job in the way that seems most sensible to them, with our help as school teachers if they ask for it. The idea that there is a body of knowledge to be learnt at school and used for the rest of one's life is nonsense in a world as complicated and rapidly changing as ours. Anxious parents and teachers say, "But suppose they fail to learn something essential, something they will need to get on in the world?" Don't worry! If it is essential, they will go out into the world and learn it.
Exams, grades and marks should be abolished because children's progress should only be estimated by _____________.
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Câu 5:
Mark the letter A, B, C or D to indicate the underlined part that needs correction in each of the following questions.
Alice in Wonderland, first published in 1865, has since being translated into thirty languages.
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Câu 6:
Mark the letter A, B, C or D to indicate the word that differs from the other three in the position of the primary stress in each of the following questions.
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Câu 7:
Mark the letter A, B, C or D to indicate the underlined part that needs correction in each of the following questions
Modern art is on display at the Guggenheim Museum, a building with an unusually design.
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