Ключевые слова: abstract, advertisement, advertising, alte, background, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, close, closeup, communication, concept, copy, design, drawing, education, element, empty, frame, grunge, grungy, horizontal, learning, lesson, macro, message, nobody, noticeboard, photo, photograph, rubbed, school, smudged, space, surface, symbol, teach, text, textured, textures, wall, white, write,