On very hot days in the summer, the large flat surface of the tail is used to help cool the beaver's body.
(the large flat surface of the tail; is used; to help cool the beaver's body; T:On very hot days in the summer) (the large flat surface of the tail; to help; cool the beaver's body)
the large flat surface of the tail the large flat surface of the tail
is used to help
to help cool the beaver's body T:On very hot days in the summer
cool the beaver's body