However, the ocean lies under a thick layer of ice that is too thick to allow sunlight to be the primary source of energy necessary for life.
(the ocean; lies; under a thick layer of ice) (a thick layer of ice; is; too thick to allow sunlight to be the primary source of energy necessary for life)
the ocean a thick layer of ice
lies is
under a thick layer of ice
too thick to allow sunlight to be the primary source of energy necessary for life