i know that 和 i know about that,有什么区别吗?

i know that 和 i know about that,有什么区别吗? I know of him 和 I know about him 和 I know him 有啥区别 I know that he is rich 和I know he is rich 有什么不同? I know that you care about That's all I know.和That's what I know.的区别 I come to know和I know有什么区别? know 和know about有什么区别 know和 know about 有什么区别? "For I know that! i know that you know that I I know that.and ______ about that blue one