Ключевые слова: background, book, books, bookstore, business, college, concepts, cover, data, dictionary, documents, education, educational, encyclopedia, expertise, graduation, group, heap, information, intelligence, isolated, knowledge, learn, learning, library, literary, literature, nobody, objects, old, open, page, paper, pile, publication, read, reading, readings, research, school, science, stack, study, studying, text, textbook, textbooks, traditional, university, white,