1.不定式做主语

　　(1)引导逻辑主语的介词：不定式的逻辑主语一般由介词for引导,但下列表示人的性格行为特征的形容词做表语时, 不定式的逻辑主语则由of引导：absurd, bold, brave, courageous, careful, careless, clever, wise, foolish, silly, stupid, good, nice, kind, thoughtful, considerate, greedy, generous, honest, modest, polite, rude, cruel, selfish, lazy, wicked, wrong。如：

　　Experts say walking is one of the best ways for a person to stay healthy. It’s clever of you to have invented such a device.

　　(2)不定式做主语补足语：

　　掌握常用不定式做主语补足语的句型。注意不定式表示的动作发生的时间，并采用相应形式。如： be said / reported / thought / believed / known / supposed + to do sth.

　　2.不定式做宾语

　　掌握要求接不定式做宾语的动词：

　　afford, arrange, attempt, claim, desire, determine, expect, fail, guarantee, endeavor, intend, pledge, pretend, resolve, request, swear, tend, venture。如：

　　Even though the children pretended to be asleep, the nurses were not deceived when they came into the room.

　　3.不定式做定语

　　(1)被修饰的名词前有序数词、形容词最高级或next, last, only, not a, the, very等限定词时，该名词用不定式做定语。如：the first woman to set foot on the moon 第一个登上月球的女性

　　(2)如果其动词要求不定式做宾语，相应的名词一般用不定式做定语。如：

　　tendency to do→tend to do, decision to do→decide to do

　　This book is an attempt to help you use English and recognize how it is used.