81. Milk is indispensable _____ the health of a motherless baby.

　　A. to

　　B. at

　　C. with

　　D. on

　　正确答案是

　　82. Modern industry abounds _____ opportunities for young men with imagination.

　　A. for

　　B. on

　　C. in

　　D. of

　　正确答案是

　　83. More than one third of the Chinese in the United States live in California， ______ in San Francisco.

　　A. previously

　　B. predominantly

　　C. practically

　　D. permanently

　　正确答案是

　　84. More than two hundred years ago the United States _____ from the British Empire and became an independent country.

　　A. got off

　　B. pulled down

　　C. broke away

　　D. dropped off

　　正确答案是

　　85. Most good writers use every means _____ to make the reader‘s way smooth and easy.

　　A. at their disposal

　　B. at their request

　　C. at their will

　　D. at their convenience

　　正确答案是

　　86. No longer are contributions to computer technology confined to any one country； _____ is this more true than in Europe.

　　A. hardly

　　B. little

　　C. seldom

　　D. nowhere

　　正确答案是

　　87. Nobody _____ that something was wrong at that time.

　　A. commented

　　B. committed

　　C. noticed

　　D. expressed

　　正确答案是

　　88. Of the thousands of known volcanoes in the world， the _____ majority are inactive.

　　A. tremendous

　　B. demanding

　　C. intensive

　　D. overwhelming

　　正确答案是

　　89. On knowing that this his novel won the Pulitzer Prize， his friends held a big party _____.

　　A. in his glory

　　B. in his honor

　　C. for his glory

　　D. for his honor

　　正确答案是

　　90. One study found that job applicants who make more eye contact are _____ as more alert， dependable， confident and responsible.

　　A. referred

　　B. perceived

　　C. recommended

　　D. presumed

　　正确答案是