Ключевые слова: arrow, black, blackboard, blue, board, business, businessman, caucasian, chalk, chalkboard, chart, class, clean, close, college, concept, diagram, draw, drawing, education, exponential, graph, graphic, hand, handwriting, holding, horizontal, line, mature, numbers, one, person, pie, red, sales, school, space, student, style, stylish, teach, teacher, text, university, white, work, write, writing, young,