Ключевые слова: background, black, blackboard, board, brush, chalk, chalkboard, change, changing, compliance, concept, countdown, crossword, date, day, deadline, drawing, education, future, game, history, learn, learning, lesson, line, management, now, paint, paintbrush, pause, planning, present, puzzle, quiz, schedule, school, solution, stop, study, success, teach, text, texture, time, timeline, timer, white, word, year,