Later I have to go to the Children's Palace to learn the piano.为什么用to ,have to 不是加原型吗?

问题描述:

Later I have to go to the Children's Palace to learn the piano.为什么用to ,have to 不是加原型吗?
75页3a

have to 后边加的原型是go
to learn表示目的,和have to 没有关系为什么用to动词不定式表示目的