Ключевые слова: adult, advice, audience, backs, blur, business, center, chairs, chart, conference, congress, convention, corporate, diagram, display, education, event, explaining, focus, foreground, graph, group, hall, hand, indoors, lecture, listening, man, meeting, multimedia, office, participants, people, person, podium, presentation, professional, professor, projector, public, rear, schedule, screen, seminar, sit, sitting, speaker, speech, view, woman,