四、  动词不定式复合结构

由介词for引导一个宾格代词或名词，后面再接上一个动词不定式或动词不定式词组，这种结构叫做动词不定式复合结构。例如：

   Here is a book for Tom to read. (for + 名词 + 不定式)

   Here is a book for him to read. (for + 代词 + 不定式)

(一)   动词不定式复合结构的句法功能: 相当于分句

1.     作主语

For me to go to work in a factory was very necessary.（相当于That I went to work…）

It takes time for both light and sound to travel.(光和声音传播都要花时间)

2.     作宾语

We think it a shame for Tom to do such a thing.(相当于that Tom did such a thing)

I found it difficult for you to do that experiment.

3.     作主语补语

The question is for you to decide. (相当于that you should decide)

My advice is for you to admit your own mistakes and shortcomings

4.     作名词修饰语

There is some work for us to do. (相当于that we have to do)

He bought some toys for his children to play with. (相当于which his children would play with)

5.    作状语

The boy stepped aside for me to pass by. (表目的)(相当于so that I could pass by)

Tom opened the window for the fresh air to come in. (表目的)

The book is too difficult for the students to read.(表结果)(相当于so…that the students cannot read it.)

The text is too long for us to learn by heart.(表结果)

6.    作同位语

Mother’s last request, for me to study law, cannot possibly be complied with.( 母亲临终的要求, 让我学法律, 那无论如何也不能遵从的)(相当于that I should study law…)

(二)   介词of引导的动词不定式复合结构

介词of也可以引导一个动词不定式复合结构, 即of+ 名词(宾格代词) + 动词不定式结构, 在句中作主语.例如:

It is nice of you to invite me.(你邀请我, 这太好了.)

It is very kind of you to come here.

It is foolish of Tom to do such things.

It was careless of him to break the cup.

介词of 引导动词不定式复合结构, 常用在以good, nice, kind, foolish, clever, silly, cruel, bad, careless 等描述人物特征或品德的形容词为主语补语的句子中. 上述各句可转换成下面的句型结构, 其意义不变.

You are nice to invite me.

You are very kind to come here.

Tom is foolish to do such things.

He was careless to break the cup.

上述转换方式，只能用在介词of引导的动词不定式复合结构在句中作主语的情况下；介词for引导的动词不定式复合结构在句中作主语时，就不能转换成以上的句型结构。例如，我们可以说：

It is important for you to come here.

但不能说:

You are very important to come here.

（三）动词不定式复合结构的判断

介词for后的名词或宾格代词是否是动词不定式的逻辑主语，应从整个句子的意思来判断。例如：It is good for us to do morning exercises every day. 此句中的for us应做状语,修饰good, to do morning exercises应是主语.

再如: He was to arrange for me to enter the Red areas.（我进入红色地区将由他来安排。） 这里不宜将for me to enter the Red areas看作是介词 for引导的不定式复合结构作arrange的宾语。此句中arrange作不及物动词用,arrange for可看作是词组动词,是一种固定搭配,有“安排”、“准备”之意。 “me”应是arrange for的宾语, 而to enter the Red areas 应是me 补语。

再如：We are waiting for Mr White to give us a talk about insects.(我们在等待怀特先生给我们做关于昆虫的报告。) 显然，are waiting for是一个不可分割的语义单位，而后的Mr White to give us a talk about insects是复合宾语结构。