Ключевые слова: back, background, blackboard, board, book, chalk, chalkboard, child, class, classroom, concept, desk, drawing, educate, education, elementary, equipment, formulas, green, handwriting, homework, horizontal, knowledge, learn, library, literary, literature, nobody, notebook, object, office, school, stack, student, studying, supplies, table, teacher, textbook, to, university, wisdom, write,