For example, although water always flows downhill, when it eroded the Grand Canyon it passed through various kinds of rock, at various velocities, at various volumes, and carried various kinds of erosional materials at various times.
(water; flows; downhill; T:always) (it; eroded; the Grand Canyon) (it; passed; through various kinds of rock; at various velocities; T:when it eroded the Grand Canyon) (it; carried; various kinds of erosional materials; T:at various times; T:when it eroded the Grand Canyon)
water it it it
flows eroded passed carried
downhill T:always
the Grand Canyon
through various kinds of rock at various velocities T:when it eroded the Grand Canyon
various kinds of erosional materials T:at various times T:when it eroded the Grand Canyon