Καθηγητής συλλογισμένος γκρίζα μαλλιά στέκεται στο μαυροπίνακα με κομμάτι κιμωλία - Φωτογραφίες & Εικόνες Αρχείου

Grey hair professor pointing on something with finger at blackboard

Happy senior lecturer holding paper plane in hand

Grey hair professor pointing on something with pencil on blackboard

Grey hair professor looking at students rising hands

Grey hair professor correcting something at blackboard

Grey hair professor pointing on something with wooden pointer

Grey hair professor talking by smartphone and looking at camera

Senior lecturer showing idea gesture

Cropped image of senior professor pointing on something with pencil on blackboard

Pensive handsome grey hair man thinking and looking at chessboard at home

Handsome grey hair man sitting at table with chessboard and looking at camera

Cropped image of professor drawing with piece of chalk at blackboard

Serious senior man writing in notebook with pencil

Thoughtful senior man with pencil and sheet of paper in front of white brick wall

Adult son and senior father gesturing while playing chess at home

Cheerful businessman in glasses voting near brick wall