I’ve learned that it is not that a man gives life to a child or even raises the child

问题描述:

I’ve learned that it is not that a man gives life to a child or even raises the child
______ decides what kind of relation between them.
横线上为什么填that?这种句子怎么分析?

it is...that...强调句型结构,强调主语not that a man gives life to a child or even raises the child,意思是“不是一个人给予孩子生命或把他抚养长大决定了他们之间的关系”