Ключевые слова: advertising, back, backpack, banner, book, bulb, calculator, concept, design, discount, educate, education, element, graphic, holiday, icon, illustration, isolated, item, knowledge, learn, line, linear, mathematics, object, outline, pen, pencil, poster, promotion, ruler, sale, school, schoolbag, september, shape, sign, student, study, supplies, symbol, teaching, text, thin, to, utensils, white,