The description we have already given is of the valley of the river before coming to the canyon.
(The description; have given; T:already) (The description we have already given; is; of the valley of the river; T:before coming to the canyon) (The description we have already given; before coming; to the canyon)
The description The description we have already given The description we have already given
have given is before coming
T:already
of the valley of the river T:before coming to the canyon
to the canyon