Making eye contact for too long is bad.
Growing up, I was taught to look adults in the eye when I was talking to them, but did you know that holding someone's gaze for too long can be a sign that you are trying to intimidate or dominate them? In a study published in Royal Society Open Science, researchers used eye-tracking technology to determine just how long was the right amount of eye contact. The results? On average, people preferred to look someone in the eyes for 3.3 seconds. Too much longer than that, and things start to get weird. So keep that in mind next time you're trying too hard to hold eye contact.
You can't hide your lyin' eyes.
Long-lasting eye contact can also indicate someone is lying. According to Psychologist World: "Overly persistent eye contact is also a sign of a person's over-awareness of the messages they are emitting. In the case of a person who is try to deceive someone, they may distort their eye contact so that they're not avoiding it — a widely recognized indicator of lying."