Hydrogen and oxygen are in the water contained in the earth and air, and oxygen is in the air mixed with nitrogen.
(Hydrogen and oxygen; are; in the water) (the water; contained; in the earth and air) (oxygen; is; in the air) (the air; mixed; with nitrogen)
Hydrogen and oxygen the water oxygen the air
are contained is mixed
in the water
in the earth and air
in the air
with nitrogen