have existed on Earth only as superheated steam that rose to the upper atmosphere, condensed, and fell as rain, which then became hot vapors again.
(superheated steam; rose; to the upper atmosphere) (the upper atmosphere; condensed; ) (rain; became; hot vapors; T:again; T:then)
superheated steam the upper atmosphere rain
rose condensed became
to the upper atmosphere
hot vapors T:again T:then