Ключевые слова: appreciation, back, background, black, blackboard, board, book, celebration, chalk, chalkboard, children, class, classroom, cognition, college, concept, congratulation, day, design, drawing, education, flat, flower, graphic, green, hand, happy, heart, holiday, international, knowledge, learn, lettering, national, notepad, object, pencil, poster, school, science, stationery, student, study, symbol, teacher, text, thank, university, world, young,