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 30 to 37.
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.
The word ‘innate’ in bold is closest in meaning to
A. effective
B. natural
C. active
D. organic
Đáp án B
Từ ‘innate’ in đậm gần nghĩa nhất với
A. hiệu quả B. tự nhiên C. năng động D. hữu cơ
‘innate’ = natural: tự nhiên, bẩm sinh
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All payments to the ICRC are _________ and are received as donations.
We oppose this war, as we would do any other war which created an environmental catastrophe.
Williams is working _______ an export company. He intends to apply _______ another job because he is not satisfied _______ the salary.
Mark the letter A, B, C or B on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
We (A) are going to visit (B) our grandparents (C) when we (D) will finish our final exams
Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation In each of the following questions.
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.
When the unemployment rate is high, the crime rate is usually also high
_______ is a situation in which large numbers of people have little or no food, and many of them die.
Let’s ask our teacher how to solve this problem _________ we can’t agree on the answer.
Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation In each of the following questions.
Mr. Thompson is learning Vietnamese _________ to read Kim Van Kieu.
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 38 to 42.
Lead poisoning in children is a major health concern. Both low and high doses of paint can have serious effects. Children exposed to high doses of lead often suffer permanent nerve damage, mental retardation, blindness, and even death. Low doses of lead can lead to mild mental retardation, short attention spans, distractibility, poor academic performance, and behavioral problems.
This is not a new concern. As early as 1904, lead poisoning in children was linked to lead-based paint. Microscopic lead particles from paint are absorbed into the bloodstream when children ingest flakes of chipped paint,plaster,or paint dust from sanding. Lead can also enter the body through household dust, nailbiting, thumb sucking, or chewing on toys and other objects painted with lead-based paint. Although American paint companies today must comply with strict regulations regarding the amount of lead used in their paint, this source of lead poisoning is still the most common and most dangerous. Children living in older, dilapidated houses are particularly at risk.
What does the author imply in the final sentence of the passage?