Ключевые слова: abstract, activity, assembly, attend, attention, background, be quiet, blur, blurred, bokeh, chair, classroom, conference, cooperate, education, hall, indoor, interior, join, learning, lecture, light, listen, man, material, meeting, mobile phone, motion, movement, moving, notebook, participate, pen, pencil, people, projector screen, room, screen, sitting, student, study, table, teach, teacher, train, tutor, unrecognizable, walking, women,