As they move, glaciers scour the landscape, picking up rocks and sediment as they carve out deep valleys.
(they; move; ) (they; carve out; deep valleys) (glaciers; scour; the landscape) Context(glaciers scour,List([14, 28))):(glaciers; scour the landscape picking up; rocks)
glaciers scour,List([14, 28))
they they glaciers glaciers
move carve out scour scour the landscape picking up
deep valleys
the landscape
rocks