新东方在线整理了2020考研英语语法，供参考。
独立主格的作用和处理方法
一、独立主格的由来
独立主格在英语中存在的主要价值还是由语言简洁的要求决定的，它的产生是从状语开始的，并且在考研中也只考查其作为状语的情况。独立主格结构为两个句子在主语不同的情况下提供了将其合并为一个句子的可能，通过简单的例子可以了解它的由来：
1、It is a hot day.
2、I stay at home.
这两个句子可以合并为一个：It being hot today, I stay at home.
其中，being 是可以被省略的，而且常常会在it being hot today之前加上介词with以表示其和一个句子的区别;这样with it being hot today 就被称为独立主格结构。
二、独立主格的作用和处理方法
通常情况下，独立主格可以表示一下几种情况：
1、表示时间
例句：The meeting being over, all of us went home.
解析：the meeting being over相当于when the meeting was over。
2、表示条件
例句：The condition being favorable, he may succeed.
解析：the condition being favorable 相当于 if the condition is favorable。
3、表示原因
例句：There being no taxis, we had to walk.
解析：there being no taxis 相当于since there was no taxis。
4、表示伴随状况
例句：Almost all metals are good conductors, silver being the best of all.
解析：这句话相当于Almost all metals are good conductors, and silver is the best of all.
5、表示补充说明
例句：We redoubled our efforts, each man working like two.
解析：这句话相当于We redoubled our efforts, and each man works like two。
三、考研实例解析
阅读中通常将带有独立主格的句子改写为两个句子。下面一起来看一个考研真题中的句子：President Bush campaigned to move Social Security to a saving-account model, with retirees trading much or all of their guaranteed payments for payments depending on investment returns.
解析：with retirees trading much or all of their guaranteed payments for payments depending on investment returns为独立主格结构，可以改写为一个句子：Retirees trade much of all of their guaranteed payments for payments depending on investment returns.使两个句子前后为因果关系。