Tom felt that he knew everybody's business better than they knew it themselves.

问题描述:

Tom felt that he knew everybody's business better than they knew it themselves.
翻译

Tom 觉得他比其他人更了解他们自个儿的事.
这里的business 是“事情,情况”的意思,类同于"It's none of your business."中的business.(不关你的事.)