So, while earthquakes were thrusting the land upward, the river was carving downward throught the rock layers, and the Grand Canyon was born.
(earthquakes; were thrusting; the land; upward) (the river; was carving; downward; throught the rock layers; T:while earthquakes were thrusting the land upward) (the Grand Canyon; was born; )
earthquakes the river the Grand Canyon
were thrusting was carving was born
the land upward
downward throught the rock layers T:while earthquakes were thrusting the land upward