Ключевые слова: 50, background, backgrounds, book, books, bookshelf, bookstore, collection, color, colored, concepts, cover, curiosity, data, document, education, expertise, frame, green, group, hardcover, horizontal, information, large, library, literary, literature, media, medium, multi, novel, objects, office, page, paper, reading, research, row, school, spine, stack, study, studying, textbook, thick, university, white, wisdom, word, write,