Equivocation
As Forbes states, people who are lying often give unnecessarily long, vague and excessively complicated answers even to closed yes/no questions. Complicated answers should alert you, especially if they come from people who otherwise always speak briefly and to the point.
Inability to keep eye contact
Eyes are a gateway to the soul and can also tell you a lot about lying. Be on your guard if someone breaks or avoids eye contact, or keeps looking all around the room. At the end of the meeting, ask that person whether they have acquainted you with all potential risks connected to their proposal. If they avert their eyes before answering, beware: they may be concealing something from you.
Covering one's mouth with one's hand
A hand placed on any part of head is usually a sign of greater or lesser nervousness. A hand placed on the mouth when talking can then be a subconscious defensive reflex of someone who is saying something that is not entirely true.
Nervous movements
For many people, leg twitching can be just a bad habit that need not mean anything serious. However, if you are talking to someone who does not have such a habit but during the conversation starts nervously tapping or shaking their leg, beware: combined with other warning signs, this could indicate nervousness caused by conscious lying.
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