Ключевые слова: activity, artificial, backdrop, background, ball, border, boundary, boy, color, competition, concept, cone, cones, equipment, exercise, field, football, game, garden, goal, grass, green, hurdle, line, marker, natural, nature, orange, outdoor, plastic, play, practice, safety, school, soccer, space, sport, sports, stripe, symbol, synthetic, team, texture, top, training, under, warm, white,