Ключевые слова: academic, aged, asking, back, blackboard, board, book, chalkboard, class, classroom, college, course, discussing, education, elder, elderly, exam, experienced, explaining, graduation, green, high, learn, learning, lecture, lecturer, lesson, man, mature, mentor, mentoring, old, older, pointing, questioning, school, science, secondary, senior, showing, study, studying, teacher, teaching, textbook, training, tutor, tutoring, university,