状语从句到独立结构(absolute construction )

状语从句的连接词

独立结构（独立主格）

如果有be动词，谓语变身过程中丢掉be动词，本质就是变成了分词结构

例子

1. 主语一直主动

When I was a little girl, I fell in love with science.

Being a little girl, I fell in love with science.

Because she knows what I need, she can provide a right answer.

Knowing what I need, she can provide a right answer.

2. 主语一致被动

As he was elected as the new president, he became prudent.

Elected as the new president, he became prudent.

3. 主语不一致被动

As her work was done, she sat down for a cup of tea.

Her work done, she sat down for a cup of tea.

完成时的保留问题

have， has， had + v-ed 统一变换成having + v-ed
本质是助动词代替了实意动词变形。

Because he has finished his home work, he is allowed to play video games.

Having finished his home work, he is allowed to play video games.

进一步的简化

be动词后面是形容词，可以删掉be动词