Chorea is an aimless and irregular, fast and involuntary movement of head and face, and four extremities.

舞蹈病临床常见以头面部及四肢无目地不规则，快速不自主的运动，呈突然发作。

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Part of its charm revolves around the rubberized tracks on its feet as well as on the extremities of each of its four limbs -- not surprisingly, these are engineered to help it maneuver in some pretty sticky situations.

ENGADGET: Carnegie Mellon's Chimp robot is reporting for duty, sir