Ключевые слова: adult, audience, auditorium, business, classroom, conference, course, crowd, education, equipment, event, furniture, group, hall, indoors, inside, instructor, large, learning, lecture, lecturer, light, listening, man, meeting, microphone, people, person, podium, presentation, public, reading, room, row, school, screen, seminar, smile, space, speaker, speech, student, students, study, teacher, teaching, training, university, white, work,