Ключевые слова: ad, advertisement, advertising, announcement, background, billboard, black, blackboard, blank, board, chalk, chalkboard, childhood, class, classroom, close, college, communication, concept, copy, copyspace, dirty, drawing, education, empty, frame, grunge, horizontal, knowledge, learn, lecture, lesson, message, nobody, note, old, primary, remember, school, scratch, space, teach, teacher, text, texture, textured, used, white, write,