1.分词短语作状语时，它的逻辑主语应该是句子的主语。
Eg.) Examining the patient, the doctor wrote down something on paper.
Hit by the arrow, he fell from the horse.
应避免写分词逻辑主语和句子主语不一致的句子。如:
Walking along the road, an accident happened. (×)
Listening to the radio, there was a knock at the door. (×)
Walking along the road, I saw an accident. (√)
Listening to the radio, I heard a knock at the door. (√)
2.但独立主格结构的逻辑主语与句子的主语不是同一个人或事。
独立主格结构－－名词普通格或代词主格+其它成分（形，副，介短，分词和不定式）（它们之间存在着逻辑上的主谓关系）
独立主格在句子中作状语，可以表示时间、原因、条件和方式、伴随。主要用于书面语,表示描述.
eg.) 1.今天是星期天，你不必去上学。
A) 用原因从句表达：
Because it is Sunday, you needn't go to school.
B) 用分词独立结构表达：
It being Sunday, you needn't go to school.
但不能写成：Being Sunday, you needn't go to school.
(因分词的逻辑主语不是句子的主语，所以句子错误。)
2.官员们都到齐了，宣布开会。
A) 用分词独立结构表达：
All the officials having arrived, the meeting was declared open.
B) 用时间状语从句表达：
After (when) all the officials had arrived, the meeting was declared open.
3. 天气允许的话，我们去颐和园。
A) 用分词独立结构表达：
Weather permitting ,we'll go to the Summer Palace.
B) 用条件状语从句表达：
If weather permits , we'll go to the Summer Palace.
4.所有的工作都完成了，你们可以休息了。
All the work done, you can have a rest.
=All the work is done and you can have a rest.
5.他看着这情景，张大着嘴。
He watched the scene, his mouth ( being ) wide open.
6. 会议结束后,他们都回家了。
The meeting (being) over, they all went home. (逻辑谓语是adj./adv 时,前面省略being)
有时,独立主格结构可以由with引出:
eg.) The child trembled, with hands red with cold.
The park is beautiful with all the trees putting on a tender green. 树叶都绿了，使得公园很漂亮。
The road is beautiful, with trees and flowers growing well here and there.
有时, 这种结构中的冠词或物主代词可省去,称为泛指结构,反之,称为特指结构.
Eg.)He came out, umbrella in hand.
=He came out, with an umbrella in his hand.
The guards stood at attention, guns on shoulders.
= The guards stood at attention, with guns on their shoulders.
3.分词固定短语：（有时表示说话人态度的分词结构已成为固定短语，不遵循其逻辑主语和句子主语一致的原则）。
eg.)1.Judging from her accent, she must be an American.
2.Genarally speaking, the living costs are relatively higher in cities.
3.Talking of the world resources , they are very limited.
4.No wonder he was taken ill, considering that he had been overworking for years.
5.Taking as a whole, the experiment was a success.