This helps keep them warm, but because it is so cold in the Arctic that they have thick under and overcoats of fur that they shed once a year, as well as a one to six inch layer of blubber under the skin.
(it; is; so cold in the Arctic that they have thick under and overcoats of fur) (overcoats of fur; shed; T:once a year) (This; helps; keep them warm) Context(This helps,List([0, 10))):(This; helps keep; them)
This helps,List([0, 10))
it overcoats of fur This This
is shed helps helps keep
so cold in the Arctic that they have thick under and overcoats of fur
T:once a year
keep them warm
them