非谓语动词是指在句子中不是谓语的动词,主要包括不定式、动名词和分词（现在分词和过去分词）,即动词的非谓语形式.非谓语动词除了不能独立作谓语外,可以承担句子的任何成分.
非谓语动词与谓语动词的相同点有
（1）如果是及物动词都可与宾语连用,例如：They built a garden.They suggested building a garden.（2）都可以被状语修饰：The suit fits him very well.The suit used to fit him very well.（3）都有主动与被动,“体”式（一般式；进行式；完成式）的变化.例如：He was punished by his parents.（谓语动词被动语态） He avoided being punished by his parents.（动名词的被动式） We have written the composition.（谓语动词的完成时） Having written the composition,we handed it in.（现在分词的完成式） （4）都可以有逻辑主语 They started the work at once.（谓语动词的逻辑主语） The boss ordered them to start the work.（动词不定式的逻辑主语） We are League members.（谓语动词的主语） We being League member,the work was well done.（现在分词的逻辑主语） (5) 否定式一般用not,并且放在非谓语动词之前
非谓语动词与谓语动词的不同点有
（1）非谓语动词可以有名词作用（如动词不定式和动名词）,在句中做主语、宾语、表语.（2）非谓语动词可以有形容词作用（如动词不定式和分词）,在句中做定语、表语或宾语补足语.（3）非谓语动词可以有副词作用（如动词不定式和分词）,在句中作状语.（4）谓语动词在句中作谓语,受主语的人称和数的限制；非谓语动词在句中不能单独作谓语,它不受主语的人称和数的限制.(5)英语中不能单独做句子的谓语.
动词不定式
动词不定式：（to）+do,具有名词、形容词、副词的特征.否定式：not + (to) do 以do为例,动词不定式的构成如下：时态/语态 主动语态 被动语态
一般时 to do to be done
进行时 to be doing
完成时 to have done to have been done
完成进行时 to have been doing
（1）一般式：不定式的一般式所表示的动作与谓语动词动作同时发生或发生在谓语动词动作之后.例如：I'm glad to meet you.很高兴见到你.He seems to know a lot.他看起来懂得很多.We plan to pay a visit.我们计划花钱去参观.He wants to be an artist.他想成为一个艺术家.The patient asked to be operated on at once.病人要求马上手术.The teacher ordered the work to be done.老师要求完成工作.（2）进行式：不定式的进行式所表示的动作与谓语动词动作同时发生,例如：The boy pretended to be working hard.男孩假装工作得很努力.He seems to be reading in his room.看起来他正在他的房间里面读书.（3）完成式：不定式的完成式表示的动作发生在谓语动词动作之前,例如：I regretted having told a lie.我后悔我说谎了.I happened to have seen the film.我偶然看过这部电影.He is pleased to have met his friend.他很高兴能遇上他的朋友.
