How to know that the human is lying on you ?

but some people can hide the truth..you cant recognize if they are lying to you..sometime other people cant lie because they are not good in lying!

The fact that they cannot really keep a story straight is really something. Granted, we all forget things, it's only human but there are times where there is a line to drawn between faulty memory and just absolute lies to say the very least. Sometimes people not only cross that line but they completely obliterate any lingering trace of it. It just makes me saddened when people feel the need to lie but they have really convinced themselves their lies are the truth. Also their voice tends to betray them. Often times if they aren't that good of a liar, they tend to sound unsure, almost as if they are trying to convince themselves. Of course some people get a bit better but then we have the problem of people who seem a bit too confident. Often times however the worst liars are those who have mastered it to such a degree where it is hard to tell because they don't feel the slightest guilt at all.