Ключевые слова: academic, blackboard, board, caucasian, chalk, chemistry, class, classroom, coat, college, concentrate, degree, education, elderly, faculty, formula, graduate, high school, intelligent, learn, lecture, lecture hall, lecturing, male, man, one, person, physics, profession, professor, pupils, school, science, scientist, secondary, senior, smile, students, study, teacher, university, white coat, wisdom, wise, write,