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Levan322001
2 năm trước
Một vật có khối lượng 100g treo vào đầu một sợi dây nhẹ, không dãn, dài 1m, đầu kia của sợi dây được cố định vào điểm C. Kéo vật sao cho dây treo hợp với phương thẳng đứng một góc 60 độ, buông vật ra và cho vật truyền với vận tốc 6m/s theo phương góc với sợi dây . Xác định a) cơ năng của vật vừa được buông ra (gốc thế năng ở vị trí cân bằng)... b)vận tốc của vật và lực căng của dây treo khi vật đi qua vị trí cân bằng... c) độ cao cực đại mà vật đạt được so với vị trí cân bằng
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I/ Use the correct word forms 1. My father drives ………………… ……(careful) 2. I want to see the ....................... of the enviroment from the local authority. ( protect) 3. There is a ............................. faucet in your kitchen. (drip) 4. We can protect the enviroment by .................. air pollution. ( reduction) 5. If we go on littering, the enviroment will become.......................... polutted. (serious) 6. The old man walked ................................ to the park. ( slow) II. Pronunciation A. Choose the word that has the underlined part pronounced differently from others 1. A. beach B. clean C. instead D. leave 2. A. nation B. international C. national D. natural 3. A. pollution B. rubbish C. cut D. truck 4. A. beach B. plumber C. volleyball D. cucumber B. Choose the word whose main stress pattern is placed differently from the others 5. A. consumer B. environment C. electricity D. pollution 6. A. energy B. appliance C. ordinary D. luxury 7. A. dynamite B. pesticide C. company D. pollution 8. A. protect B. litter C. prevent D. reduce III. Choose the best answer 1. Is he really ………………….that you can’t come here ? A . disappoint B . disappointed C . disappointing D .to disappoint 2. It is necessary …………………….forests A . protect B . protected C . protecting D . to protect 3. If I understand I ………… explain it again to you A . will B . would C . am D . was 4. We are talking about the preservation of ………………..resources A . nature B . natural C . naturally D .naturalize 5. If he………..a student, he must wear school uniform A . is B . are C . be D . was 6. If you have ………money , you can travel abroad this summer A . many B . a lots C . a lot of D . lot of 7. Don’t go up that ladder. It doesn’t look ………………... a. safe b. safely c. safety d. unsafe 8. If you are a student , you can get a discount …….books A . for B . in C . on D . with 9. The air in the city is very ………… A . pollute B . polluted C . pollution D . pollutant 10. The accident happened because of driving ............. A . careful B . carefully C . careless D . carelessly 11. They made their living by …………………..fish in this lake everyday A . catch B . to catch C . catching D . caught 12. I suggest ………….. to the movies A . go B . to go C . going D . went 13. Two people were killed and the driver of the car was ………… injured. a. serious b. seriously c. extreme d. high 14. I was disappointed that I did so ……………… in the exam. a .bad b. badly c .good d. well 15. Don’t go up that ladder. It doesn’t look ………………... a. safe b. safely c. safety d. unsafe 16. I’ll be in trouble if I…………….. my passport . a. lose b. will lose c. lost d .would lose 17. We couldn’t go on a picnic as planned……………. it was raining hard. a. however b. but c. because d. so 18. What about using buses instead ………………. motorbikes? a. for b. of c. from d. in 19. Who’s going to look………………your children when you’re at work? a. for b. up c. after d. at 20. I suggest……………… to the movies. a. go b. to go c. going d. went 21. Before you go to bed, please turn…………. all the lights. a. on b. off c. up d. down 22. If he…………. a student, he will get a discount on books. a. is b. was c. were d. will be 23. My sister sings very…………………… a. beauty b. beautiful c. beautifully d. beautify 24. Mrs Ha should get a ……………… to check the cracks in the pipes. a. teacher b. doctor c. plumber d. mechanic A/ Rewrite these sentences as directed 1. Let’s invite Hoa and Huong to join our club. I suggest that……………………………………………………………………. 2. Although she was not beautiful, she took part in a beautiful contest. She wasn’t beautiful but .............................................................................. 3. My team won the first prize. I’m delighted. ( Combine into one , using adj+ that clause) I’m …………………………………………………………… 4. She couldn’t come to class because of her illness. As…………………………………………………………………………… 5. He got wet. He forgot his umbrella. ( Combine into one, using THEREFORE) He.. ………………………………………………………………………… B.Write a complaint letter with the words given Dear Mr President, 1. I / write /the noise caused / Karaoke bar / near / house ……………………………………….………………………………………………... 2. They play / music / loudly / so / I / not study / evening / sleep / night ……………………………………………………………………………………… 3. They / should / lower / volume/ when / it / 9 p.m ………………………………………………………………………………………… 4. I / look forward to / hear / you / see / how / solve / problem …………………………………………………………………………………….. Sincerely

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