考研英语之所以难是由于文章中到处都充斥着长难句，也就是句子不仅长而且结构复杂。而读懂这些长难句是我们解题的关键之所在。要想读懂，我们得学会去拆分，去识别出句子所包含的重要语法现象，其中关于独立主格结构是一个重难点。那么，接下来，由老师梳理下相关知识点。
(一)基本构成形式
名词(代词)+现在分词/过去分词/形容词/副词/不定式/名词/介词短语
1.名词(代词)+现在分词
There being no bus,theyhad to walk home.
2.名词(代词)+过去分词
She was listening attentively in class, hereyes fixed on the blackboard.
3.名词(代词)+不定式
在此结构中，动词不定式和前面的名词或代词若存在着逻辑上的主谓关系，动词不定式则用主动的形式;若是动宾关系，则用被动形式。
The four of us agreed on a division of labor, each to translate a quarter of the book.
Many trees, flowers, and grass to be planted, our newly-built school will look even morebeautiful.
4.名词(代词)+形容词
Computers very small, we can use them widely.
5.名词(代词)+副词
The meeting over, our headmaster soon left the meeting room.
6.名词(代词)+名词
His first shot failure，he fired again.
7.名词(代词) +介词短语
Every afternoon a very old woman hobbled past the old house，a vast load of firewood on her back.
(二)with/without引导的独立主格结构
with/without+宾语(名词/代词)+宾语补足语，宾语通常由名词或代词充当，但代词一定要用宾格。在with (without)的复合结构中，多数情况下with能省略，但without不能省略。
The girl hid her box without anyone knowing where it was.
Without a word more spoken, she left the meeting room.
The kid feels excited with so many places of interest to visit.
(三)独立主格结构的句法功能
独立主格结构在句中一般作状语，表示时间、条件、原因、伴随状况等，可以看成是一个状语从句的省略。
1.作时间状语
The governor pondering the matter，more strikers gathered across his path.
2.作条件状语
Weather permitting，they will go on an outing to the beach tomorrow.
3.作原因状语
The boy leading the way, we had no trouble finding the strange cave.
4.作伴随状语或补充说明
Ten students entered for the competition, the youngest a boy of 12.
(四)注意事项
1.独立主格结构的逻辑主语与句子的主语不同，它独立存在。名词或代词与后面的分词等逻辑上是主谓关系，独立主格结构一般有逗号与主句分开。
The president assassinated, the whole country was in deep sorrow.
2.动词不定式表示动作没有发生或即将发生，动词-ed形式表示动作已经结束，动词-ing形式往往表示动作正在进行。
The manager looks worried，many things to settle.
(事情还没有处理，而且是由经理本人来处理，用不定式to settle，表示将来的时间)
The manager looks relaxed, many things settled.
(事情已经处理好了，用过去分词settled表示动作已经结束)
The food being cooked, the boy was watching TV.(两个动作同时进行)
3.独立主格结构与分词短语都可以转换为状语从句。但是独立主格结构转换为状语从句后，它有自己的逻辑主语，与主句的主语不一致;而分词短语转换为状语从句后，从句的主语与主句的主语一致。
If time permits, we'd better have a holiday at weekends.(条件状语从句)
Time permitting, we'd better have a holiday at weekends.(独立主格)
When we see from the hilltop, we can find the city more beautiful.(时间状语从句)
Seeing from the hilltop, we can find the city more beautiful.(现在分词)
