Lecture with formulas on the blackboard in front of studentsLecture with formulas on the blackboard in front of students
A gray block of rock on the shore, against the background of a lilac skyA gray block of rock on the shore, against the background of a lilac sky
Waiting for the way on the background of autumn treesWaiting for the way on the background of autumn trees
Two dry autumn leaves lie on the rain-soaked table of an outdoor cafeTwo dry autumn leaves lie on the rain-soaked table of an outdoor cafe
A field of pink cosmos on the background of mountains and cloudsA field of pink cosmos on the background of mountains and clouds