Since humus is porous, it allows air, nutrients and water to get to the grass roots.
(humus; is; porous) (it; allows; air, nutrients and water to get to the grass roots) Context(it allows,List([23, 32))):(air, nutrients and water; to get; to the grass roots)
it allows,List([23, 32))
humus it air, nutrients and water
is allows to get
porous
air, nutrients and water to get to the grass roots
to the grass roots