They have gray-brown fur in winter that changes to reddish-brown in the summer.
(They; have; gray-brown fur in winter that changes to reddish-brown in the summer) (gray-brown fur in winter; changes; to reddish-brown; T:in the summer)
They gray-brown fur in winter
have changes
gray-brown fur in winter that changes to reddish-brown in the summer
to reddish-brown T:in the summer