为什么 To do today's homework without the teacher's help is very difficult.的主语中心词为to do?
问题描述：
为什么 To do today's homework without the teacher's help is very difficult.的主语中心词为to do?
答
To do today's homework without the teacher's help是本句主语,without the teacher's help是修饰,所以To do today's homework是主语中心词.