Ключевые слова: abstraction, cancel, cancelled, carcass, clear, close, closed, closure, colored, colorful, contour, cross, delete, destroy, disagree, erase, error, exit, flat, frame, framework, geometric, gradient, grid, icon, kill, linear, lines, mesh, network, no, polygon, polygonal, rainbow, reject, remove, sign, spectral, spectrum, stop, structure, symbol, trash, triangle, web, wireframe, wrong, x cross,