Answer:
How they act. If a person acts in an odd way that you don't think is normal, then you can be suspicious of them. It can be simple gestures like twitching, shaky hands, signs of nervousness or a different emotion that may be concerning. They may also get involved with you, they may tell a lot of lies, and pressurize you to do something. They may also ask for your info discreetly, and try to be normal about it when it really isn't.
Step-by-step explanation: