Textbooks say the most spectacular canyon in the world, the Grand Canyon, was formed by stream erosion over a hundred million years.
(Textbooks; say; the most spectacular canyon in the world, the Grand Canyon, was formed by stream erosion over a hundred million years) Context(Textbooks say,List([0, 13))):(the most spectacular canyon in the world; was formed; by stream erosion; T:over a hundred million years)
Textbooks say,List([0, 13))
Textbooks the most spectacular canyon in the world
say was formed
the most spectacular canyon in the world, the Grand Canyon, was formed by stream erosion over a hundred million years
by stream erosion T:over a hundred million years