Question

So many diretors being absent,the board meeting had to be put off.是什么语法句式？

Answer 1

So many diretors being absent,the board meeting had to be put off.是一个使用了独立主格结构的句子。独立主格结构主要用于描绘性文字中，其作用相当于一个状语从句，常用来表示时间、原因、条件、行为方式或伴随情况等。
句子本身可以表达为Because so many diretors were absent,the board meeting had to be put off.前半句是一个原因状语从句，为简化，可使用独立主格形式来表示，形式通常为: n. + -ed/-ing形式; n. + 不定式 ; n. + 介词短语; n. + 形容词; n. + 副词.句子中就使用了n. + -ing形式来表示一种伴随的状态。