Ключевые слова: abstract, advertisement, advertising, announcement, back, background, billboard, black, blackboard, blank, board, chalk, chalkboard, class, classroom, closeup, concept, design, drawing, dust, education, element, empty, frame, grained, grunge, horizontal, idea, inspiration, learning, letter, message, note, notice, old, pattern, photograph, rubbed, school, slate, smooth, space, surface, symbol, texture, textured, wall, wallpaper, white, writing,