A szürke haj professzor helyesbítéséről valamit a táblára oldalnézete - Stock fotó és kép

Smiling grey hair professor holding piece of chalk

Senior lecturer holding piece of chalk and looking away

Grey hair professor pointing on something at lecture hall

Side view of grey hair professor drawing with piece of chalk at blackboard

Smiling grey hair professor holding stack of books with apple on top

Smiling grey hair professor sitting on table with laptop

Senior lecturer pointing on something in lecture room

Senior lecturer holding book and looking away

Elderly man in bow tie and blue jacket using smartphone isolated on grey

Serious senior man in tweed suit and glasses looking at camera

Portrait of smiling grey hair man looking at camera at home

Pensive handsome grey hair man holding book and looking at camera

Cropped shot of senior man with pencil and sheet of paper

Positive senior man talking on smartphone and pointing with finger isolated on grey

Elderly man in shirt and jacket using smartphone isolated on grey

Bearded senior writer reading manuscript with magnifying glass