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Hai công nhân nếu làm chung thì 12 giờ hoàn thành công việc. Họ làm chung với nhau trong 4 giờ thì người thứ nhất chuyển đi làm việc khác, người thứ hai làm nốt phần công việc còn lại trong 10 giờ. Hỏi người thứ hai làm một mình thì trong bao lâu sẽ hoàn thành công việc đó.
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I. Multiple choice: Choose the correct word/ phrase to fill in the blank 1. I will look for another job ………………………………… my salary is increased. a. if b. when c. as d. unless 2. Why were you so ………………………………… when I saw you yesterday? a. friendless b. unfriendly c. friendly d. friendship 3. Cars and trucks are ………………………………… from driving in the city center. a. prohibited b. preserved c. leaked d. treasured 4. Bob doesn’t go to work today. He ……………………………… ill . a. may be b. maybe c. ought to be d. will be 5. They put garbage bins around the schoolyard to prevent lazy students ……… littering. a. with b. from c. for d. by 6. It rained ………………………………… for three days. a. continue b. continues c. continuing d. continuously 7. Don’t …………………………………. We have to keep our schoolyard clean and tidy. a. litter b. put trash c. waste d. reduce garbage 8. We are all slowly destroying the earth by ………………………………… our environment. a. setting b. minimizing c. polluting d. confining 9. This river is polluted: a lot of fish died and floated on the …………………………………. a. water line b. water front c. water surface d. water surfing 10. They took him for a French man because his French was so ………………………………. a. good b. well c. better d. bad 11. Instead of being excited about the good news, Tom looked ………………………………. a. different b. indifferent c. differently d. indifferently 12. There is no need ………………………………… you to shout. I can hear you. a. with b. to c. of d. for 13. If you aren’t going to live in the house, why ………………………………… you sell it? a. do b. don’t c. wouldn’t d. didn’t 14. I hope they ………………………………… be pleased when they saw the photographs. a. can b. could c. would d. should 15. These bags are made of……………………… You can use them to carry heavy things. a. paper b. silk c. plastic d. glass I1/ Guided Cloze Test Green Peace is an (1)___________________ environmental organization dedicated to preserving the earth’s natural (2)__________________ and its diverse plant and animal life. Green Peace was (3)______________in Vancouver, British Columbia, Canada, (4)____________ 1971 by members of the Don’t Make a Wave Committee, a small group (5)____________ was opposed to nuclear weapons testing by the United States military in Alaska. The group renamed itself Green Peace to reflect the broader goal of creating a green and (6)_________________ world. Green Peace has about 3 million (7)_________________ and more than 40 offices in 30 (8)______________. Its international headquarters are in Amsterdam, Netherlands. 16. a/ nation b/ national c/ international d/ internationally 17. a/ disasters b/ languages c/ dumps d/ resources 18. a/ found b/ founded c/ to found d/ founding 19 a/ on b/ in c/ from d/ since 20. a/ which b/ who c/ whom d/ whose 21. a/ disappointingb/ interesting c/ amazing d/ peaceful 22. a/ workers b/ members c/ conservationists d/ students 23. a/ schools b/ villages c/ countries d/ cities III/ Read the passage. Then write True (T) or False (F) for each sentence below: There is too much carbon dioxide in the air. When oil, gas, and coal burn, they create a large amount of carbon dioxide. We send five million tons of carbon dioxide into the atmosphere every year. This amount will double in fifty years. This carbon dioxide lets sunlight enter the Earth’s atmosphere and heat the Earth. However, it doesn’t let as much heat leave the atmosphere and enter space. It is like a blanket. The heat can pass from the sun through the blanket to warm the Earth. The heat stays there and cannot escape through the blanket again. Scientists call this the greenhouse effect. 24. When we burn oil, gas or coal, they give out carbon dioxide . ……………. 25. Every year about five million tons of carbon dioxide are sent into the atmosphere.……………. 26 This carbon dioxide heats the Earth. ……………. 27. The blanket keeps carbon dioxide inside it. …………….

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