在独立主格结构中，动词不定式和它前面的名词或代词存在着逻辑上的主谓关系。


His mother to come tonight，he is busy preparing the dinner.他母亲今晚要来,他正在忙着准备饭菜。（= As his mother is to come tonight, he is busy preparing the dinner.）


——will you go to the comcert tonight 你今晚去听音乐会吗？


——sorry.So many exerise-books to check,I rially can't afford any time.对不起，有这多的作业要批，我真的抽不出时间。


（＝Because I shall check so many exercise-books tonight,I really can't afford any time.）


The four of us agreed on a division of labour,each to translate a quarter of the book.我们四人同意分工干，每人翻译全书的四分之一。


（＝The four of us agreed on a division of labour and each is to translate a quarter of the book.）


Many trees,flowers,and grass to be planted,our newly-built school will look even more beautiful. 种上许多的树，花和草后，我们新建的学校将看上去更美。


(=If many trees,flowers,and grass are planted,our newly-built school will look even more beautiful.)