Ключевые слова: background, binder, binding, blank, blue, book, business, collection, color, colorful, cover, document, education, group, handbook, hardcover, heap, information, isolated, learning, literature, notebook, objects, office, orange, page, paper, pile, reading, red, research, ring, school, space, spine, spiral, stack, study, text, textbook, traditional, university, vertical, vibrant, white, wisdom, yellow,