101.A hundred things remain____________（do）.
Key：to be done。动词不定式被动形式，表示将要被做或值得被做。例如：It's not fit to be seen. 不堪入目
It's not to be trusted. 不足为凭
This is not to be mentioned to outsiders. 不足为外人道。
Treat other people as you would like to be treated; be considerate.推己及人
One has done nothing to be ashamed of. 俯仰无愧
One pretends to be surprised. 佯装惊诧
Everything that is good is sure to be praised and everything bad is sure to be exposed. 好人好事有人夸，坏人坏事有人抓。
Being poor is nothing to be ashamed of.人穷并不可怕。
102. One doesn’t know whether___________（laugh） or cry.
Key：to laugh 。“特殊疑问词（+名词）+动词不定式”结构。例如：One hesitates about what move to make. 举棋不定
The day is long to him who knows not how to use it. 百无聊赖
One understands what to love and what to hate; know whom to love and whom to hate.爱憎分明
103. It's too busy ___________（attend）to something.
Key：to attend。“too…to”结构。例如：It's too far away to be helped. 鞭长莫及
It’s too late to plug the leak when the boat is in midstream.船到江心补漏迟。
A man too young to grow a beard is not dependable.嘴上没毛，办事不牢。
“so…as to”结构。例如：Be so buried in one's work as to forget one's meals. 发愤忘食
One enjoys oneself so much as to forget to go home.流连忘返
One is so happy as to forget home and duty. 乐不思蜀
104.Let the tiger ___________（return）to the mountain.
Key：return。Let/make/see/hear/watch,etc sb/sth +动词原形,表示将要或经常做。例如：Long to see one’s son become a dragon. 望子成龙
Try to make sb. do what he is unwilling or unable to. 强人所难
Let him who would enjoy a good future waste none of his present. 让那些憧憬着美好未来的人一点都不要虚度现在。
105.One does all one can do ____________（catch）up.
Key：to catch。“do what/all/everything sb can/could（do）+动词不定式一般式”， 表示目的。
例如：One does what little one can to help.添砖加瓦