You're sitting down to a nice family dinner and note your teenager is behaving oddly. When you ask about his day, he says nothing happened, but your parenting alarm is going off. He's not saying anything, but his body language is definitely talking. Perhaps you can read his body language and see if he's anxious about something.
Watch for crossed arms across the chest. People cross their arms when they feel angry, defensive or anxious, but they're trying to hide it.
Note breathing. Often when people are anxious they breathe faster and shallower than usual, or they may breathe a little more deeply. They also may clear their throat a few times, like they're going to say something, but change their mind. Sighing is also an indication of anxiety.
Pay attention to movement. Quick, twitchy movements indicate anxiety. So do frequent position changes and fidgeting.
Keep an eye on the eyes. If the person won't hold eye contact with you or her eyes dart all over the place, she's probably anxious.
Look for nervous chewing, especially if the person is not a chewer by nature. Often when people are anxious they chew on the backs of pens, pencils, their nails, even their lips.
See if the person is shaking. If his hands are trembling and he can't keep his feet still, or if his knees are shaking up and down, chances are he's anxious about something.