Ключевые слова: abc, abstract, ad, advertisement, advertising, advice, alphabet, association, background, blackboard, board, bulb, bulletin, chalkboard, circular, classroom, color, decision, education, fancy, font, glass, icon, idea, imagine, insignia, lacunae, letter, mark, mud, nature, notation, notice, notification, pattern, plan, plank, proclamation, publicity, sand, school, schoolroom, sign, soil, style, summer, symbol, teaching, texture, think, visualize,