(4)否定式：(to)前加not：

He pretended not to have seen me.

(5)不定式的逻辑主语有两种情况(用for sb.或of sb.)：

It's high time for us to plant trees.

It's very kind of you to say so.

动词的过去分词

(1)作定语

及物动词的过去分词，既表被动又表完成；不及物动词的过去

分词，只表示完成。单个的分词作定语，放在它所修饰的词

的前面;分词短语作定语，放在它所修饰的词的后面。例如：

A broken cup is lying on the floor.

The meeting held yesterday was very important.

(2)作表语：

表状态，与句子主语是被动关系。例如：

He seemed quite delighted at the idea.

The city is surrounded on three sides by mountains.

(3)作状语

动词的过去分词相当于副词，可以在句子中作状语，与句子主

语是逻辑上的主谓关系，两者往往是被动关系，即主语是过去

分词动作的承受者。

Seen from space, the earth looks like a ball.

Compared with the people in Iraq, we are much happier.

名词加过去分词，构成独立结构，用作状语。

All things considered, her paper is of greater value than yours.

(4)作宾补

作宾语补足语的过去分词，大都来自及物动词。分词与宾语是

被动关系。不及物动词的过去分词作宾补,与宾语是主动关系,

表示动作已经发生。

I saw the house broken into.

There is something wrong with my radio. I will have it repaired.

The emperor ordered the cloth (to be) woven for him at once.

He came in, with his hands tied at the back.

动词的-ing形式

动词的-ing形式相当于名词、形容词、副词等,也保留了动词的某些特征。

(1)作主语：

Talking is easier than doing.

It's no use talking about it.

(2)作宾语：