Polar bears survive the bitter cold of the Arctic winter because they are kept warm by their thick fur coats, and the layer of fat beneath.
(Polar bears; survive; the bitter cold of the Arctic winter; because they are kept warm by their thick fur coats, and the layer of fat beneath) (they; are kept; by their thick fur coats)
Polar bears they
survive are kept
the bitter cold of the Arctic winter because they are kept warm by their thick fur coats, and the layer of fat beneath
by their thick fur coats