The air we breathe consists of about 78% nitrogen and 21% oxygen (O2) with trace gases making up the rest.
(The air; breathe; we) (The air we breathe; consists; of about 78% nitrogen and 21% oxygen) (trace gases; making up; the rest)
The air The air we breathe trace gases
breathe consists making up
we
of about 78% nitrogen and 21% oxygen
the rest