B77. I need some more food. Would you like to give me two more apples?
选择：B. some more; two more
解析：修饰名词定语的排序为“限定词（包括不定代词） + 数词 + 形容词 + 名词”，因此应该是“限定词some + 形容词more + 名词food”和“数词 two + 形容词more + 名词apples”
A78. --- Do you spend a lot of time on computer? --- No, but I spend much time in doing my homework.
选择：A. on; in
解析：spend time 后面如果是具体事物，应该用介词on，即spend … on sth.，如果是表示做某事（动名词），应该用介词in或者省略介词，即 spend … (in) doing sth.
D79. --- Would you like________ the environment? --- I don’t know. What can I do?
选择：D. to help save
解析：
1、would like 后面只能跟不定式作宾语，表示愿意做某事，因此应该用 to help
2、help 后面也需要不定式作宾语，也可以省略 to，即 help do sth.。本题选项中的help save 就是省略用法。
C80.____ is wrong to copy other students’ homework.
选择：C. It
解析：句中的真实主语是后置的不定式短语，it是形式主语，即it is wrong to do sth. （做某事是不对的）
B81. It is bad for your eyes playing computer games too much.
选择：本命题有错，没有别的选择，只能用to play
解析：本句与上句C80属于同一种用法，只不过是不定式多了逻辑主语for your eyes，即 it is … for… to do sth.
特别说明：当 it is后的表语如果是表示有益或无益的 good, bad, helpful, useless, useful等词汇，只能用动名词作真实主语，因此此题正确的选择是选项中没有的playing。
C82. —______ go to the theatre together with me? —Good idea.
选择：D. Why not
解析：本句表示建议，这种语气可以用How about、What about和Why not多种方法表达，但是前者的 about是介词，后面只能跟动名词短语going to the theatre。Why not go to the theatre是Why don’t we go to the theatre的省略（省略了助动词 do和主语 we）。
B83. Miss Yang does a helpful job in the school library, many student are grateful ___ her.
选择：B. to
解析：“（因某事）感谢某人”的表达法是be grateful to sb. (for sth.)
A84. Although he was a child, he tried to find ways to help people enjoy life more.
选择：A. to help ; enjoy
解析：第一空用不定式 to help是ways 的定语，即“帮助人的方式”；第二空的道理同D79，help 只能用不定式作宾语。
D85. --- Can I use your mobile phone? --- Sorry, my mobile phone _____ .
选择：D. needs repairing
解析：“人需要做某事”用need to do，“事物需要被做”用need doing 或者need to be done；my mobile phone是单数第三人称，因此用needs repairing。
C86. - ___ do I need to take ? - It’s helpful for you to take a map and a mobile phone if you get __ .
选择：C. What else, lost
解析：else只能放在疑问代词或不定代词之后。get 后应该是作表语的过去分词lost，相当于被动语态be lost。