Gia đình bạn An, bạn Bình dùng máy bơm để bơm nước từ dưới đất lên bồn chứa trên cao ở cùng độ cao 6 m. Máy bơm A nhà bạn An bơm được trọng lượng nước 5000 N lên bồn trong 150 s. Máy bơm B nhà bạn Bình bơm được trọng lượng nước 20000 N lên bồn trong 500 s. Máy bơm nhà bạn nào mạnh hơn? Vì sao? Câu 5: Một người công nhân đẩy một thùng hàng di chuyển trên mặt sàn nằm ngang. Trong thời gian 50 giây, thùng hàng đi được quãng đường 20 m, biết lực đẩy của người đó có phương song song với mặt sàn và có độ lớn 100 N. a. Hỏi lực đẩy của người đó có sinh công cơ học không? Vì sao? b. Tính công suất của người công nhân.

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26. If I had taken that English course, I ………..much progress. a. had made b. would have made c. made d. would make. 27. If I were in your place, I ……….a trip to England. a. will make b. had made c. made. d. would make. 28. If I ………….. you , I’d save some of your lottery winning. a. be b. were c. am d. was 29. If the car ……….. larger, we would have bought it. a. had been b. have been c. has been d. been 30. If I had enough money, I ……… abroad to improve my English. a. will go b. should go c. would go d. should have go to 31. If it …….. convenient, let’s go out for a drink tonight. a. be b. was c. were d. is 32. If you ……. time, please write to me. a. have b. have had c. had d. has 33. If you had the chance, ………… you go finishing? a. did b. would c. may d. do 34. Trees won’t grow ……….. there is enough water. a. if b. when c. unless d. as 35. If you ………. to my advice in the first place, you wouldn’t be in this mess right now. a. listen b. had listened c. will listen d. listened 36. I wish I …….. you some money for your rent, but I’m broke myself. a. can lend b. could lend c. would lend d. will lend 37. If someone ……… into the store, smile and say, “ May I help you?” a. comes b. came c. would come d. could lend 38. If you stay up late the previous night, you ………. sleepy the next morning. a. feel b. to feel c. feels d. will feel 39. If Peter ………., Sarah will be sad because she wants to meet him very much a. comes b. do not come c. does not come d. will come 40. If his teeth still …….., he will have to go to the dentist’s again. a. hurt b. hurts c. to hurt c. will hurt

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions. Question 43: The flag over the White House is risen at dawn every day by a color guard from the United States armed forces. A. over the White House B. is risen C. at dawn D. by Question 44: Facebook.com’s server IP address could not find in Google Chrome browser because of the error of Internet connection. A. Facebook.com’s B. could not find C. because of D. Internet connection Question 45: The passengers, tired after a very long trip, was relaxing in every available seat in the airport lobby. A. The B. very C. was relaxing D. available 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. Question 46: “Be careful or you may get lost and run out of money.” She said. A. She advised me to be careful or I might get lost and run out of money. B. She warned me to be careful or I had to get lost and run out of money. C. She ordered me to be careful and I might get lost and run out of money. D. She told me to be careful if I got lost and run out of the money. Question 47: I’m sure it wasn’t Mr Phong you saw because he’s in Hanoi. A. It couldn’t be Mr Phong you saw because he’s in Hanoi. B. You mustn’t have been Mr Phong you saw because he’s in Hanoi. C. It can’t have been Mr Phong you saw because he’s in Hanoi. D. Mr Phong is in Hanoi, so you might have seen him. Question 48: Success in the academic field depends on your number of qualifications. A. You are successful in the academic field, so you have more qualifications. B. Your number of qualifications is a result of your success in the academic field. C. The more success you are in the academic field, the more qualifications you have. D. The more qualifications you have, the more successful you are in the academic field. Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions. Question 49: The basketball team knew they lost the match. They soon started to blame each other. A. Not only did the basketball team lose the match but they blamed each other as well. B. Hardly had the basketball team known they lost the match when they started to blame each other. C. No sooner had the basketball team started to blame each other than they knew they lost the match. D. As soon as they blamed each other, the basketball team knew they lost the match. Question 50: I picked up my book. I found that the cover had been torn A. When picking up my book, the cover had been torn B. On picking up my book, I saw that the cover had been torn C. The cover had been torn when my book picked up D. Picked up, the book was torn

11. What would happen if you ……………..to work tomorrow? a. don’t go b. didn’t go c. won’t go d. wouldn’t go. 12. We ‘ll get wet if we ………….out. a. go b. did go c. went d. had gone. 13. If I go shopping, I ………some food. a. buy b. will buy c. would buy d. would have bought. 14. If I find it, I ………you. a. will tell b. would tell c. had told d. told. 15. What would you do if you……………a million dollars? a. would win b. win c. had won d. won. 16. They ‘d be hurt if I ………………. a. don’t go b. didn’t go c. hadn’t gone d. wouldn’t go. 17. If we took the 6: 30 train, we…………too early. a. would have arrived b. arrived c. will arrived d. would arrive. 18. If I had known you were in hospital, I …………to see you. a. will go b. would go c. went d. would have gone. 19. If I …………., I would have said hello. a. had seen b. see c. saw d. would see. 20. I…………..out if I hadn’t been so tired. a. will go b. went c. would have gone d. would go. 21. If I ………..a camera, I would have taken some pictures. a. have b. had c. would have d. had had. 22. You won’t pass the examination……………you study more. a. as long as b. unless c. if d. whether. 23. If only I …………you wanted to invest money in business. a. had known b. knew c. have known d. know. 24. If I were to leave my country , I ……………disappointed. a. probably be b. would have been c. will be d. would be. 25. If he hadn’t wasted too much time, he…………….in his examination. a. would fail b. wouldn’t fail c. wouldn’t have failed. d. won’t fail.