These are how to detect some facial expressions. Enjoy reading!
SURPRISE: The upper eyelids and brows rise, and the jaw drops open.
FEAR: The eyes widen and the upper lids rise, as in surprise but the brows draw together. The lips stretch horizontally.
CONTEMPT: This is the only expression that appears on just one side of the face. One half of the upper lip tightens upwards.
DISGUST: The nose wrinkles and the upper lip rise while the lower lip protrudes.
HAPPINESS: The corners of the mouth lift in a smile. As the eyelids tighten, the cheeks rise and the outside corners of the brows pull down.
SADNESS: The eyelids droop as the inner corners of the brows rise, and in extreme sadness, draw together. The corners of the lips pull down, and the lower lip may push up to a point.
ANGER: Both the lower and upper eyelids tighten as the brows lower and draw together. Intense anger rises and the upper eyelids as well. The jaw thrusts forward, the lips press together, and the lower lip may push up a little.