The formation of the Grand Canyon and its multiple rock layers was the product of many forces, including uplift and subsidence of the land, erosion, volcanism, and the movement of land masses over large portions of the earth.
(The formation of the Grand Canyon and its multiple rock layers; was; the product of many forces, including uplift and subsidence of the land, erosion, volcanism, and the movement of land masses over large portions of the earth)
The formation of the Grand Canyon and its multiple rock layers
was
the product of many forces, including uplift and subsidence of the land, erosion, volcanism, and the movement of land masses over large portions of the earth