As they do with sadness, the features fall, the cheeks relax downward and sometimes inflate in a sigh of discouragement. A bead forms under the lower lip. Yawning causes the eyes to close and the mouth to widen, sometimes asymmetrically.
All you need are a few strokes (half-closed eyelids, absent look, sunken mouth) to make the face look shut down.
The dark circles under the eyes are accentuated, and the disheveled effect of the hair underscores the impression of fatigue.
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