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hoanganh692004
2 năm trước
Khí đốt cháy: _Metan cháy thành ngọn lửa xanh mờ. _Axetilen cháy thành ngọn lửa sáng. _Benzen cháy thành ngọn lửa kém sáng hơn axetilen và có nhiều khói đen Hãy giải thích các hiện tượng trên.
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Make questions for the underlined words or phrases : 1. …………………………………………… It takes me 15 minutes to walk to school. 2. …………………………………………….. My village is to the north of the city 3. ………………………………………………… I go to school by bike. 4. ……………………………………………………… It’s about 2 kilometers from my house to school 5. …………………………………………………….. No, there isn’t ( there isn’t park in my village ) 6. ……………………………………………………….. She will travel to Ha Noi next week. 7. ……………………………………………………… They went to the countryside once a month last year. 8………………………………………………………………….. Nam went to bed early last night because he has a test today. 9. …………………………………………………………. Yes. He helps on the farm after school. 10 ………………………………………………………………….. No . I haven’t finish my report .

II. Read the passage, and choose the correct answer A, B, C or D for each question. Many people still believe that natural resources will never be used up. Actually, the world’s energy resources are limited. Nobody knows exactly how much fuel is left. However, we also should use them economically and try to find out alternative sources of power. According to Professor Marvin Burnham of the New England Institute of Technology, we have to start saving coal, oil and gas before it is too late; and solar power is the only alternative. However, many people do not approve of using nuclear power because it’s very dangerous. What would happen if there was a serious nuclear accident? Radioactivity causes cancer and may badly affect the future generations. The most effective thing is that we should use natural resources as economical as possible. 1. How much fuel left? A. there is a lot of fuel B. Let’s use it as much as we would like C. No one knows exactly D. It will never be used up 2. According to professor Mavin Burnham,__________. A. solar power is the only alternative B. we have to save coal, oil, and gas C. A and B are incorrect D. A and B are correct 3. Radioactivity from nuclear power . A. alters a new kind of energy B. is necessary to cure diseases C. can have good effects on the future generations D. causes cancer and has bad effects on the future generations 4. We should use coal, oil, and gas . A. as much as possible B. carelessly C. as economically as possible D. all are incorrect 5. According to the passage, using nuclear power is . A. interesting B. dangerous C. safe D. cheap

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