Ключевые слова: academic, aged, back, blackboard, board, chalkboard, checking, class, classroom, college, course, demonstrating, discussing, education, exam, experienced, explaining, graduation, green, heavy, holding, homework, learn, learning, lecture, lecturer, lesson, man, mentor, mentoring, notes, old, paper, papers, pile, pointing, presenting, school, science, secondary, showing, study, studying, teacher, teaching, training, tutor, tutoring, university,