Ключевые слова: banner, black, blackboard, board, chalk, chalkboard, child, closed, concept, demonstration, design, desk, doodle, drawing, drawn, employees, green, grunge, jobs, kids, labor, poland, polish, problem, protest, protesters, raise, reform, salary, school, sign, strike, student, teacher, teachers, text, union, vote, white, word, work, worker, written,