1. D??2. D??3. C??4. B??5. A??6. C??7. A??8. B??9. D??10. A
11. B?12. A?13. C?14. B?15. D?16. C?17. A?18. C?19. D?20. B
21. D?22. B?23. B?24. A?25. C?26. C?27. A?28. D?29. B?30. A
31. B?32. C?33. D?34. A?35. D?36. D?37. B?38. C?39. C?40. A
41. D?42. D?43. C?44. B?45. A?46. B?47. B?48. C?49. B?50. D
51. C?52. D?53. D?54. C?55. A?56. A?57. B?58. A?59. D?60. C
61. B?62. A?63. D?64. C?65. A?66. D?67. C?68. A?69. A?70. B
71. progresses ? progress?72. (room) ? (room) with
73. voice ? sound(s)/noise(s)?74. their ? its/the
75. ringing ? ring?76. by ? for
77. the (work), / (work)?78. careful ? carefully
79. passed ? passing?80. if ? but/but/yet/though/although