英文中的非谓语包括三种：不定式、动名词和分词(过去分词、现在分词)。
不定式，即不一定是什么词性的成分，可以当名词、形容词和副词来使用，能够在句子充当除谓语外的任何成分。
20.1 不定式的作用
- 做主语，一般采用it作形式主语，而将to do表示的主语置于句尾，用for来引出不定式的逻辑主语
- It is impossible for us to master English in a short time.
- 英文思维中没有“we are impossible…”的表达，improssible只能用来形容物，因此要用it is impossible for us to do结构
- 作宾语
- 动词+to do，不定式的逻辑主语与主句主语一致
- I hope to see you again.
- This company refused to cooperate with us.
- 动词+疑问词+to do
- I wonder who to invite.
- 动词+it+宾补+to do，动+宾+宾补结构必须用it作形式宾语（动词不定式或that从句都需要用it，名词短语和what从句则不用）
- I think it hard to answer the question in one go.
- The anthropological concept of “culture”, like the concept of “set” in mathematics, is an abstract concept which makes possible immense amounts of concrete research and understanding.
- 动词+to do，不定式的逻辑主语与主句主语一致
- 作宾语补足语
- Allow me to drink to your success!
- 作定语，名词+to do
- 宾语关系，修饰名词逻辑上充当不定式的宾语
- I have a letter to write.
- She has four children to take care of.
- 主语关系，修饰名词逻辑上充当不定式动词的主语
- The man to help to you is Johnson.
- The next train to arrive is from New York.
- 同位语关系，名词与不定式短语构成相互说明关系，所修饰名词应当是由与不定式搭配的词演化而来
- The need to love and to be loved seems universal.
- 状语关系，所修饰名词在逻辑上充当不定式的状语
- There are two basic ways to see growth: one as a product, the other as a process.
- 补语关系，所修饰名词在逻辑上充当不定式的补语
- The thing (for you) to be these days is a gold-collar.
- 宾语关系，修饰名词逻辑上充当不定式的宾语
- 形容词+to do，需要根据形容词的语义特点来分析句子主语和to do之间的逻辑语义关系
- 宾语关系，形容词侧重于事，但表层结构为人作主语，深层结构为不定式做逻辑主语，可以根据深层结构对句子进行变换
- He is interesting to listen to. = It’s interesting to listen to him.
- He is easy to fool. = It’s easy to fool him.
- 不定式动词不用被动（仅限形容词+to do的形式）！ He is easy to be fooled.
- 不定式后面不能再加宾语! He is easy to fool him.
- 宾语关系，形容词侧重事件特性，物做主语，不能进行句子变换
- The book is interesting to buy.
- The book is interesting to read.
- 主语关系，形容词通常为对人的评价，可以用it is句型改写
- He is kind to help us. = It is kind of him to help us.
- 主语关系，形容词表情感态度，无法改写
- He is glad to help us.
- 主语关系，形容词用来说明不定式动词，可作为副词修饰不定式动词
- He is show to react.
- 宾语关系，形容词侧重于事，但表层结构为人作主语，深层结构为不定式做逻辑主语，可以根据深层结构对句子进行变换
- 作状语，主要是目的状语，注意不定式的逻辑主语和主句主语应当一致，或用for引出逻辑主语；only to do, so…as to do/such as to do, too…to do引导的不定式表结果状语
- I quate others in order better to express my own self.
- For any adhesive to make a really strong bond, the surfaces to be glued must be absolutely clean and free from moisture or grease.
- We hurried to the railway station, only to find the train had just left.
- 独立使用的不定式
- 不定式作独立成分，修饰整个句子，to begin with, to tell the truth, to make a long story short, so to speak, to be breif/exact/frank/honest, to say the lesat, to say nothing of
- To begin with, on behalf of all your American guests, I wish to thank you for the incomparable hospitality.
- 不定式引导独立的句子，表达愿望、担心、惊讶等强烈情感，to think, to imagine
- To imagine even for a minute that I would do a thing like that on purpose.
- 不定式作独立成分，修饰整个句子，to begin with, to tell the truth, to make a long story short, so to speak, to be breif/exact/frank/honest, to say the lesat, to say nothing of
20.2 不定式的逻辑主语
逻辑主语都是针对非谓语而言，表示非谓语的执行者，区别与句子结构上的句法主语
- for+名词/代词+to do
- The father will be proud for his son to win the gold medal.
- 在部分形容词+to do结构中，需要使用of+名词/代词+to do
- It’s wise of you not to argue with your boss.
20.3 不定式的时态和语态
不定式的六种形式：to do, to be done, to have done, to have been done, to be doing, to have been doing
- 被动式，当主句中没有出现执行者或不定式所修饰的成分是不定式动作的承受者，则不定式用被动式
- It’s an honor for me to be invited to address the international conference.
- The book is not allowed to be taken out of the library.(双重被动)
- 完成式，表示不定式是在谓语动作之前的动作，通常谓语表态度情感、观点、推断
- I’m sorry to have kept you waiting so long.
- Humans are believed to have evolved from the primate species.
- The rain seems to have stopped.
- 进行时，表示与谓语动作同时发生动作，通常谓语为seem, happen, pretend
- He pretended to be sleeping when she came in.
- 完成进行时，表不定式动作在谓语动词之前已经开始并一直在持续
- He seems to have been sitting there all day.
20.4 省略to的不定式
- 在某些动词的复合宾语中，如使役动词let, make, have, 感觉动词see, hear, watch, notice, feel, observe
- The minister had his secretaries arrange a press conference.
- 在特定的句型结构中
- 部分固定短语：had better, would rather, would sooner, would just as soon, cannot but, cannot choose but, cannot help but
- You looked so beautiful and lovely I couldn’t help but fall in love with you.
- More than, rather than, other than, than后面不加to的不定式
- She preferred to give herself up rather than hide herself.
- do nothing/anything/everything but do句型中
- I have nothing to do but wait.
- 在why(not)+do句子中
- Why not take a holiday?
- 在并列结构中，to经常被省略，但若两个不定式之间有对比含义时，需要保留
- Do you want to have lunch now or wait till later?
- The need to love and to be loved seems universal.
- 在一些固定的动词搭配中，make do, make believe, let drop, let fall, let fly, let slip, let go of, hear say, leave go of
- 部分固定短语：had better, would rather, would sooner, would just as soon, cannot but, cannot choose but, cannot help but