All she would do was to go home.

(4)用作宾补：

I warned the boy not to be late again.

He saw her leave the house.

She was seen to leave the house.

He often helps me (to) learn English.

With no one to help him, he can't do it.

With so many problems to settle, the manager can't leave for

holidays.

【注意】用于不带to的不定式作宾补的的动词有：feel, hear, see,

notice, observe, watch, listen to, look at, have, make, let等。但

变为被动语态时需要带to。例如：

I noticed her enter the office.

We heard him sing every day.

Santa's father made her promise that she wouldn't write to me

or send me any word.

(5)用作定语：

I have nothing to write (to write on/to write with).

I was the first to come to school.

We have no time to think about rest.

(6)用作状语：常表示原因、结果、条件、目的等。

He stopped to talk to an old man.(目的)

I rushed to the station, only to find the train already gone.(结果)

He was happy to hear the news.(原因)

另外：in order to; so as to引导目的状语，"为了,以便";so...as to

引导结果状语，"太......以致......"。

(7)用在疑问词后面，如what to do,构成不定式复合结构,相当于名

词，作主语、宾语和表语。例如：

The question is where to get a computer.(表语)

I really don't know what to do.(宾语)

How to get rid of the pollution is still a problem.(主语)

【注意】不定式也有一定的时态和语态；有否定式、完成式、进

行式、被动式等和自己的逻辑主语：

(1)被动形式：

He asked to be sent to the front.

(2)进行式：

He pretended to be listening attentively.

(3)完成式：

He is said to have gone abroad.