Ключевые слова: art, background, blackboard, board, class, classroom, coach, course, demonstrate, demonstration, design, education, element, front, graphic, group, icon, illustration, instruction, isolated, learner, learning, lecture, lecturer, lesson, object, person, pictogram, pointer, presentation, pupil, school, seminar, sign, silhouette, simple, speaker, speech, students, study, symbol, teach, teacher, trainer, training, view, web, white,