Ключевые слова: adult, audience, back, briefing, business, businessman, cinema, coaching, colleagues, conference, congress, convention, corporate, crowd, dark, discussion, education, event, forum, group, head, indoors, institute, lecture, light, listeners, listening, manager, many, meeting, movie, participants, people, person, presentation, professional, public, rear, seminar, silhouette, sitting, spectator, speech, teaching, training, view, watching, workshop,