Bài 1 cho a+b+c=d CMR a^3+b^3+c^3-d^3=3(c-d)(ab+dc) Moi nguoi giup minh voi a

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Exercise 1 : Choose the best answer : 27. It is necessary ……… his father everything? A. to tell B.tell C. telling D.tobe told 28."Let’s have a break ,, Not , now . I didn’t want to stop …….yet A. study B. to study C. for studying D.studying 29. She enjoyed ……… the violin in the morning A. practising playing B. practising to play C. to practise playing D.to practise to play 30. My father is considering …. his job . A. to change B.change C. changing D.changed 31. I prefer ……. the book at home to the ……….. boring film . A. reading/ seeing B. to read/ see C. read/ seeing D. reading/ see 32. His parents wouldn’t allow him …………across the big river. A. to risk swimming B. risking to swim C. for risk to swim D. risking swimming 33. It is no use……………. what has been done. A. to regret B. regretted C. regretting D. regret 34. They looked forward very much to ………. her again A. be meeting B. have met C.meeting D. meet 35. Would you mind ………… your radio a little please ? A. turn off B. turning off C. to turn down D.turning down 36. Only one of these books is ………………… A. worth to read B.worth being read C. worth of reading D. worth reading 37. I advised him ……… too much about the result of the test A. not to worrying B.not worrying C.don’t worry D.not to worry 38. My father hates ………. He never allows me ……. A. to smoke / to smoke B. smoking/smoking C.smoke/smoke D.smoking/to smoke 39.Do you remember………….me at a party last year? A.meet B. to meet C.meeting D.met 40. Remember ………… my best regards to her when you write A.sending B.send C. sent D. to send 41. I never forget ………… the beautiful place for the first time. A. visit B. visiting C. visited D. to visit 42. Our T.V set is out of order and needs …………… A. repairing B. to be repairing C. repaired D. be repaired 44. I’m busy now . I’m sorry I can’t help ……….. the flowers A. to water B. watering C. watered D. waters 45. He likes ……………, but he doesn’t like……….. today because he doesn’t feel well A. swimming/ to swim B. to swim/ swimming C. swimming/ swimming D. to swim/ to swim 46. What I wanted was …………….as quickly as possible A. getting the work done B. to get the work doing C. getting the work doing D. to get the work done 47. It is compulsory for students in some schools ………… uniforms. A. to wear B.wear C. wearing D. worn 48. This classroom needs ……….. It’s very dirty A.clean B.cleaning C . to clean D.cleaned 49.At school , students usually take part in ……… money for charity A.raised B.to raise C.raising D.raise 50.Do you enjoy ……..cartoon? A. watching B.to watch C.watch D.watched

II. Choose the best answer 1. They never want me (eat)………………………………… whatever I want to. 2. They didn't expect their children (be)………………………………….. serious during their absence. 3. Where do you want her (meet)……………………………………… you? 4. I would like you (stop)…………………………………………….. complaining 5. He gave up (smoke)……………………………………….. many years ago. 6. I hate (sleep)…………………………………………… in the dark. 7. Would you mind (post)……………………………………….. this letter for me. 8. He went out without (say)……………………………………… good bye. 9. After they had finished (eat)………………………………………. they drove away. 10. I couldn't avoid (meet)………………………………… him because he's my neighbour. 11. My son is studying medicine and he wants (specialize)………………………………. in paediatrics. 12. They enjoy (spend) ……………………………….their holidays with us in the South of France. 13. I suggest (call)……………………………. to reserve a table at the restaurant. 14. I don't mind (stay)………………………………….. to keep an eye on Mary. 15. He refused (answer) ………………………………without the presence of his lawyer. 16. I hope (see) …………………………….you soon in better form. 17. My parents decided (welcome)………………………………. my boyfriend to dinner next Sunday. 18. We got tired of (wait)……………………….. for the weather (clear)……………………………. 19. Did you advise him (see) ……………………………………. the doctor? 20. It’s too hot now. Why don’t we go (swim) …………………………………? . 21. I like (eat)………………………………….. pizza.