Ключевые слова: african, american, back, backpack, bag, boys, childhood, children, classmates, copy, education, elementary, energetic, energy, ethnic, friends, friendship, fun, grade, group, happy, hispanic, horizontal, kid, kids, knowledge, learning, length, lesson, medium, outdoors, people, preschool, primary, pupil, pupils, racing, rucksack, running, rushing, school, schoolboys, schoolchildren, schoolgirls, space, students, together, usa, view, youth,