There being no bus,he had to walk home.为什么用there be?

题目

There being no bus,he had to walk home.为什么用there be?

答案

There being no bus=Because there is no bus,这的确是一个独立主格结构.由一个名词或代词作为逻辑主语,加上一个分词、形容词、副词、动词不定式或介词短语作为逻辑谓语构成,这种结构在形式上与主句没有关系,通常被称为独立主格结构.
独立主格结构主要起状语作用,相当于一个状语从句,多用来表示行为、方式、伴随等情况,有时也可用来表示时间、原因、条件等情况.
1.Time permitting,we can have a walk around the playground after supper.如果时间允许,晚饭后我们可以到操场上散散步.
2.The last guest to arrive,our party was started.最后一位客人到了,我们的晚会就开始
3.The lights off,we could not go on with the work.
4.When we see from the hilltop,we can find the city more beautiful.
Seeing from the hilltop,we can find the city more beautiful.从山顶上看,我们发现这个城市更美了
独立主格结构的特点：
　　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.
　　2）名词或代词与后面的分词,形容词,副词,不定 式,介词等是主谓关系.
　　3）独立主格结构一般有逗号与主句分开.