Ключевые слова: background, background of squared copybook sheet, blue, cellulose, cellulose fibers, checkered, child, children, clean, close up, copybook, cross, education, empty, exam, fibers, geometry, grid, grid paper, learning, macro, material, math, notebook, paper, physics, rough, school, sheet, square, squared, squared paper, stripe, study, surface, texture, textured, wallpaper, white,