Câu hỏi:
15/04/2020 528Read 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
Which of the following is the main topic of the passage?
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Câu hỏi trong đề:
24 ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 Môn thi: TIẾNG ANH !!
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Trả lời:
Giải bởi Vietjack
Chọn A
Kiến thức: Đọc hiểu
Giải thích:
Câu nào sau đây là chủ đề chính của đoạn văn?
A. âm thanh do cây cối tạo ra
B. sự rung động do côn trùng tạo ra
C. tác dụng của côn trùng trên cây.
D. nhiệm vụ của Sở Lâm nghiệp Hoa Kỳ
Thông tin: It’s a sound you will probably never hear, a sickened tree sending out a distress signal
Tạm dịch: Đó là một âm thanh mà bạn có thể sẽ không bao giờ nghe thấy, một cái cây bị bệnh gửi ra một tín hiệu đau khổ
Nhà sách VIETJACK:
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 1:
_____ his income of current job is relatively low, he finds it difficult to make ends meet.
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Câu 2:
_____ our own interests is one of the most important factors in choosing a job.
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Câu 3:
It was wrong of you not to ask your parents’ permission before deciding to quit your job
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Câu 4:
Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions
I can say for certain that your father will hit the ceiling when he finds out you’ve played truant
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Câu 5:
_____ Socialist Republic of Vietnam is a country with a great patriotism through its history
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Câu 6:
When _____ about the theft, the suspect said that he had taken no part in it
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Câu 7:
75% of the world’s population habitually consume caffeine, which up to a point masks the symptoms of sleep deprivation
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