This dry region was carved by erosional forces into valleys, ridges and hills that were later modified by glaciers and subsequently flooded by the sea.
(This dry region; was carved; by erosional forces; into valleys, ridges and hills) (valleys, ridges and hills; were modified; by glaciers; T:later) (valleys, ridges and hills; flooded; by the sea; T:subsequently)
This dry region valleys, ridges and hills valleys, ridges and hills
was carved were modified flooded
by erosional forces into valleys, ridges and hills
by glaciers T:later
by the sea T:subsequently