Madre e hija saludando las manos y mostrando el corazón mientras tienen video chat - Metraje y vídeo de stock

Portrait of happy young man crazy scientist laughing in class at desk looking at camera wearing glasses and casual clothing. People, emotions and profession concept.

Novosibirsk, Russia, November 4, 2016. The meeting with the departments of the City Hall and the city of Moscow lawyers

Patient lady teacher explaining subject on tablet, schoolboy does not understand

Novosibirsk, Russia, November 4, 2016. The meeting with the departments of the City Hall and the city of Moscow lawyers

4K Portrait smiling academic man and woman studying math formulas on blackboard

4K Portrait smiling academic man and woman studying math formulas on blackboard