Ключевые слова: abstract, advertising, back, backdrop, background, banner, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, close, closeup, communication, concept, copy, dark, design, dirty, drawing, education, empty, frame, grey, grunge, horizontal, isolated, learning, macro, message, nobody, old, photo, rubbed, school, slate, smudged, space, surface, teacher, text, texture, textured, wall, white, write,