Ключевые слова: back, background, blackboard, board, chalk, chalkboard, childhood, class, classroom, college, concept, desk, drawing, educate, education, elementary, equipment, formula, formulas, green, handwriting, homework, intelligence, knowledge, learn, learning, lecture, lesson, library, mathematics, maths, object, office, old, rustic, school, student, study, studying, surface, table, teach, teacher, text, to, university, wisdom, wood, wooden, write,