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wendychu2003
2 năm trước
Để ứng phó với khô hạn và nhiễm măn xảy ra hàng năm, một hợp tác xã đã thuê 3 máy bơm nước cho cánh đồng của mình. Nếu cả ba máy cùng bơm thì xong sớm hơn máy thứ nhất bơm một mình là 28 giờ; sớm hơn máy thứ hai bơm một mình là 48 giờ và bằng một nửa thời gian máy ba bơm một mình. Nếu mỗi máy bơm riêng một mình thì bao nhiêu giờ mới hoàn thành công việc.
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21. The air in many big cities has become _______________ A. peaceful                            B. noisy                        C. polluted                     D. quiet 22. They will live in __________houses in the future. A. hi-tech                                         B. paper                        C. water                        D. ocean 23. We can reuse __________ A. water                                  B. air                            C. bottles                   D. iron 24. We shouldn’t __________rubbish on the street. A. throw                                              B. wrap                       C. turn off                  D. take 25. Turn __________the lights when we go out. A. on                                                 B. off                           C. of                            D. out 26. Planting more __________to reduce pollution. A. rice                                                 B. flowers                  C. trees                       D. houses 27. Walking to school will help __________air pollution. A. reduce                               B. reuse                         C. recycle                        D. refill 28. Which one is different? A. running                              B. during                         C. swimming                  D. fishing 29. I think “Tom and Jerry is the best ______________      “          A. film                                     B. sport                        C. newsreel                    D. cartoon 30. My house is ______________to the supermarket.                  A. to the left                           B. behind                        C. near                        D. next 31. Karate is a form of martial ___________                  A. fighting                              B. skill                              C. sports             D. arts 32. This small ___________ is used to play table tennis.            A. racket                                 B. stick                        C. bat                          D. hoop 33. The news programme attracts millions of  __________ at 7 p.m. A. newsreaders             B. weatherman            C. MC                          D. viewers 40. It is a good idea to __________ our clothes with our friends or cousins. A. Change                              B. Swap                         C. Turn                         D. Send 41. If people turn off all electric appliances in one hour all over the world, they can save a lots of __________ . A. Electric                               B. Electrical                    C. Electrician                  D. electricity 42. Don’t throw rubbish into the river because you will make it __________ A. Greener                             B. Dirty                         C. Cleaner                       D. Fresher 43. If there is a rubbish bin in every class, the classroom will become______ A. Harmful                             B. Lighter                        C. Dirtier                         D. Cleaner 44. Reduce, reuse, recycle is said to encourage people to waste less, by using less and using things again, in order to __________ the environment. A. Harm                                  B. Damage                      C. Pollute                        D. Protect 45. These three Rs __________ reduce, reuse and recycle. A. Stand up                            B. Stand for                   C. Ask for                   D. Means Giúp mk vs hứa 5 sao

1.      Super car will __________water in the future. A. go by                                  B. run at                        C. run on                    D. travel by 2.      We will have a __________to take care of our health. A. home robot                        B. doctor robot             C. teaching robot             D. worker robot 3.      In the future, I will live __________because I like swimming. A. in the mountain                   B. on the Moon             C. on the ocean             D. under the ground 4.      We might have a __________TV so we can watch TV programs from space. A. wire                                    B. wireless                      C. wiring             D. wires 5.      You have to throw the ball into the net when you play___________ A. basketball                         B. football                        C.tennis                        D. badminton 6.      _________ is a kind of film making people laugh. A. documentary             B. cartoon                      C. music                        D. comedy 7.      VTV1is a ___________ television channel in Viet Nam. A. local                                   B. international            C. national                      D. multi-  national 8.      The news programme attracts millions of  __________ at 7 p.m. A. newsreaders            B. weatherman      C. MC              D. viewers 9.      If we __________ waste paper, we will save a lot of trees. A. Repeat                                B. Recycle                  C. Rewrite                       D. Remark 10. If we plant more trees in the schoolyard, the school will become a__________ place. A. Darker                                B. clearner                       C. Dirtier                                    D. More polluted 11. Do you think we should put a __________ bin in every classroom in order to keep it clean?       A. Reusable                           B. Recycled                     C. Recycling                    D. Recyclable 12.  My brother and I will give last year’s clothes to __________ instead of throwing  them away. A. Shop                                   B. People                        C. Charity                          D. Survey 13. It is a good idea to __________ our clothes with our friends or cousins. A. Change                              B. Swap                         C. Turn                         D. Send 14. You should put the food in a reusable box __________ plastic bags. A. By                                       B. Instead of                C.Because of                  D.Without 15. If we plant more trees in the schoolyard, the school will become a__________ place. A. Darker                                B. clearner                       C. Dirtier                                    D. More polluted 16. Football is an _________game. A. outdoor                                 B. indoor                        C. individual                             D. fun 17. Mai likes _________weather because she can go skiing. A. hot                                             B. cold                                C. rainy                       D. windy 18. You should wear _________to protect your eyes from the chlorine in the water. A. glasses                               B. goggle             C. goggles                       D. glass 19. Quang is a good badminton player . I cannot _______him. A. win                                      B. defeat                               C. control                          D. hit 20. You must learn the __________ of the game before playing. A. rules                                      B. law                                  C. agreement                      D. sayings Giúp mk vs hứa 5 sao

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