A 75 76 happens when the four-kilometer-wide piece of comet enters the Earth's 77 . 　　The sun is hidden by clouds of dust and the temperature falls to almost zero, 78 crops. Wars break out for food and only 10 million people remain. The human beings are 79 the danger of 80 out. 　　

　　高三英语限时阅读训练（十四）

　　完形填空

　　36. A 37. B 38. A 39. C 40. D

　　41. B 42. B 43. B 44. C 45. D

　　46. C 47. B 48. A 49. A 50. C

　　51. A 52. D 53. C 54. D 55. D

　　任务型阅读

　　71. faster 72. than 73. destroying 74. drowning 75. massive

　　76. explosion 77. atmosphere 78. mining 79. facing 80. dying