Steam is water that has heat energy added to it, (becoming a gaseous form of water) and loses it's volume (returning to liquid form) if cooled.
(Steam; is; water that has heat energy) (water; has; heat energy added to it) (heat energy; added; to it) (Steam; becoming; a gaseous form of water)
Steam water heat energy Steam
is has added becoming
water that has heat energy
heat energy added to it
to it
a gaseous form of water