Ключевые слова: adult, advantage edge, attention, audience, auditorium, backs, blur, business, coaching, competitive, conference, congress, crowd, discussion, european, event, foreground, forum, group, information, knowledge, learn, lecture, listeners, male, man, many, margin, meeting, men, participants, people, person, presentation, profit, public, rear, room, row, seated, seminar, speaker, training, watching, woman,