They observe a variety of living and nonliving things associated with soil, conduct soil investigations, and identify some human effects on soil.
(They; observe; a variety of living and nonliving things) (living and nonliving things; associated; with soil, conduct soil investigations, and identify some human effects on soil)
They living and nonliving things
observe associated
a variety of living and nonliving things
with soil, conduct soil investigations, and identify some human effects on soil