73. B essential
74. A touch
75. D acquire
76. C possession
77. A only
78. A with
79. D encourage
80. A interesting
81. B broaden
82. C Upon
83. B sake
84. B suffer
85. A field
86. A radical
翻译87-91答案
87. Our efforts will pay off if the results of the research can be applied to the exploration of new technology.(能应用于新技术的开发)
88. I can’t boot my computer now. There must be something wrong（一定出了毛病）with its operating system.
89. Leaving one’s job, no matter what kind (of job it is),（无论是什么工作）is a difficult change, even for those who look forward to retiring.
90. Compared with the place in which/where I grew up, (与我成长的地方相比)this town is more prosperous and exciting.
91. Not until he had finished the mission(直到他完成使命)did he realize that he was seriously ill.