Ключевые слова: background, big, blank, book, color, concept, concepts, copy, cover, data, document, education, element, encyclopedia, history, horizontal, information, isolated, knowledge, law, learning, letter, library, literary, literature, media, new, object, open, page, pages, paper, print, publication, reading, research, school, science, sheet, single, story, study, studying, text, textbook, university, white, wisdom, write, yellow,