独立主格: 有两个主语，一个主语可以将谓语动词，一个只能加非谓语动词
主语A+非谓语//本质上是---状语从句
Spring coming, the tree are turning green。As spring comes
名词+非谓语// 主动 ing 被动(不管任何时态) been done 时态 将来用 to do/ to be done
Weather permitting（if weather permits）, they will go on an outing to the beach womorrow
The work done == After the work had been done, we went home
An important lecture to be given tomorrow, As an important lecture to be given tomorrow,
the professor has to stay up late into the night.
练习： 去掉连词，变成两个句子，根据法则：只能有一个谓语动词，故而用独立主格
As the girl stared at him(the girl staring at him),he din‘t konw what to say.// the girl staring at him, he din‘t konw what to say
because her glasses were broken// her glasses broken, she could‘t see the words on the blackboard
If nobody comes tomorrow(nobody coming tomorrow), we‘ll cancle the party.
An air accident happended to the plane, nobody (was)alive
so many people abasent , the meeting had to be called off.
The meeting being over they all went home
she sat at the table, head down ready to begin the long letter.
名词+介词短语 // 不能加形容行无阻代词或者冠词
The boy goes to the classroom, book in hand.
The boy goes to the classroom, with a book in his hand. //
There being PK it being
There being nothing else to do. we went home// 有或者没有
It being a holiday, all the shops were shut. // 是
名词/代词 非谓语
形容/副词
介词短语 ==== 状语从句
There/it being 名词
With介词 不能加句子 ，不是连词是一个状语 his work finished/having been finished, he gladly accepted it
There being no taxi, we have to on foot walk
Such being the case, There are no ground to justify your compliants