I know what you mean与I know for a fact that …看起来是不是有些相似，那么它们分别是什么意思,区别在哪里呢？让杭州国际优朗英语的果果老师先带大家看两段对话：
情景模拟1：
I get very worried when my daughter won't answer her mobile phone .
I know what you mean. My daughter's just the same .
I usually imagine that something terrible has happened.
But usually she's having too much fun to answer .
情景模拟2：
I've heard that Mr Jones is thinking of selling his house .
Mr Jones is selling his house . I know that for a fact .
Really ?Did he tell you that he was ?
No , but I know for a fact that he was in the estate agent's office yesterday .
I know what you mean用于高速别人自己能明白他的啥意思，理解他的处境，往往因为有相似的经历。
例句：
That has never happened to me ,but I know what you mean . It must be terribly annoying .
我虽然从未经历过这种事，但我能理解。这事一定令人很生气。
I know what you mean . I've got the same problem myself .
我能理解你，我自己也遇到过同样的问题。
I know for a fact that …指知道一个事实，一件事情。告诉别人意见自己完全肯定的事情时，会用它强调自己要说的不是流言蜚语，也不是毫无根据的谣言。
例句：
I know for a fact that her mother disapproves of what she's doing .
我确实知道她母亲不赞同她所做的事情。
They say that their new neighbour is a millionaire .But I know for a fact that he's not as wealthy as he pretends to be .
他们说他们的新邻居是个百万富翁，但我敢肯定他是假装富有。
I know for a fact that she earns more than her husband .
我确实知道她挣钱比她丈夫多。
最后让优朗的果果老师来总结一下吧，I know what you mean简单地的说就是“我理解”，I know for a fact that …简单地说就是“我知道”。是不是很好记？
