Ключевые слова: abstract, amusing, background, ban, blocked, blue, caution, cheerful, closeup, code, danger, deny, design, emotion, entrance, forbidden, impotence, joke, object, pattern, permission, prohibition, red, regulatory, restricted, safety, security, sign, signboard, signpost, smile, smilie, smooth, space, square, stop, surface, symbol, texture, textured, tile, unit, unused, venereal, white,