Complex sentence: A more environmentally-friendly bonfire design, known as a beacon due to its pyramid shape, is enclosed in a metal cage, and made from willow chips, made from willow trees which re-grow within a year of being cut down.
Split into simpler sentences: A more environmentally-friendly bonfire design, known as a beacon due to it's pyramid shape. It is enclosed in a metal cage, and made from willow chips, made from willow trees which re-grow within a year of being cut down.