在英语中，不作句子谓语，而具有除谓语外其他语法功能的动词，叫做非谓语动词。非谓语动词有动词不定式（the Infinitive）；动名词（the Gerund）；现在分词（the Present Participle）；过去分词（the Past Participle）。
They built a garden.
They suggested building a garden.
The suit fits him very well.
The suit used to fit him very well.
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）
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）
否定式：not + (to) do
I'm glad to meet you.
He seems to know a lot.
We plan to pay a visit.
He wants to be an artist.
The patient asked to be operated on at once.
The teacher ordered the work to be done.
The boy pretended to be working hard.
He seems to be reading in his room.
I reGREtted to have told a lie.
I happened to have seen the film.
He is pleased to have met his friend.
To finish the work in ten minutes is very hard.
To lose your heart means failure.
It is very hard to finish the work in ten minutes.
It means failure to lose your heart.
Her job is to clean the hall.
He appears to have caught a cold.