They took soil samples to see if the grass was richer in that area;
(They; took; soil samples; to see if the grass was richer in that area) Context(They took,List([0, 9))):(They; took soil samples to see; if the grass was richer in that area) Context(They took to see,List([0, 29))):(the grass; was; richer in that area)
They took,List([0, 9)) They took to see,List([0, 29))
They They the grass
took took soil samples to see was
soil samples to see if the grass was richer in that area
if the grass was richer in that area
richer in that area