Ключевые слова: background, blood supply, brief, caution, caveat, cramp, danger, dehydration, epilepsy, gravid muscle, hyperkinesia, internal secretion, involuntary, leg, muscle, muscle fatigue, nervous system, neurosis, paroxysmal, reduction, road, road sign, sharp pain, sign, signpost, sky, spasm, sudden, sunset, tetanus, thigh, twilight, twitching, warning, warning sign,