Humus is the rich, fertile soil that is formed by the decomposing of plant and animal matter.
(Humus; is; the rich, fertile soil that is formed by the decomposing of plant and animal matter) (the rich, fertile soil; is formed; by the decomposing of plant and animal matter)
Humus the rich, fertile soil
is is formed
the rich, fertile soil that is formed by the decomposing of plant and animal matter
by the decomposing of plant and animal matter