Ключевые слова: academic, back, blackboard, board, books, chalkboard, class, classmates, classroom, college, demonstrating, discussing, education, educational, expensive, explaining, graduate, high, learning, lecture, lecturer, lesson, man, many, mentor, pile, pointing, presenting, professor, school, science, scientific, scientist, secondary, showing, stack, student, study, studying, teacher, teaching, textbooks, to, too, training, tutor, tutoring, university, woman,