He said to Kate. "How is your sister now?"的主语是

He said to Kate. "How is your sister now?"的主语是
“二随宾”是指直接引语变间接引语时，若从句中的主语及宾语是第二人称。或被第二人你所修饰。。如果引号外的主句没有宾语。也可以用第一人称，如：
He said to Kate. "How is your sister now?"→He asked Kate how her sister was then。


网上这样说的，什么意思，“从句中的人称要跟引号外的主句的宾语一致”什么意思