Petroleum, or crude oil, comes from deep in the earth, and is the product of thousands of years of decaying plant and animal matter.
(Petroleum, or crude oil; comes; from deep in the earth) (Petroleum, or crude oil; is; the product of thousands of years of decaying plant and animal matter)
Petroleum, or crude oil Petroleum, or crude oil
comes is
from deep in the earth
the product of thousands of years of decaying plant and animal matter