Ключевые слова: alertness, blue, cable, city, city life, city street, color image, communication, danger, day, education, electricity, environment, exploration, factory, fence, fun, guidance, horizontal, industry, journey, learning, no people, north america, outdoors, pollution, road, road sign, road trip, rural scene, safety, security, sign, sky, smog, spain, street, symbol, tourism, tower, traffic, tranquility, transportation, travel, usa, vertical,