
(copyright Paula Becker/Lobster Press)
This boy fears the teacher will think he's cheating on a test because his friend is trying to get an answer from him.
"Fear" usually includes lots of lines and sweat droplets shooting from the head area, maybe an exclamation point or two or three to show the seriousness of the situation, sprinkle that with some small curvy lines around the body to denote a shudder or shaking, big eyes with worried eyebrows, and a slightly open, down-turned mouth or maybe showing some teeth (like an upside down smile). Optional: bring a hand up to the mouth like the characters biting his fingernails.
That's how "fear" looks in the cartoon world, anyway. :)