Ключевые слова: accessory, back, background, black, blue, centimeter, child, class, college, color, copy, design, education, element, equipment, geometry, item, kid, knowledge, learn, learning, length, lesson, light, math, measure, measurement, measuring, millimeter, nobody, object, office, one, plastic, pupil, ruler, school, space, stationery, student, study, studying, supply, text, tool, top, university, view, work,