Remember that you must add heat energy to change a liquid into a gas, and you must remove heat energy to change a gas into a liquid.
(you; must remove; heat energy; to change a gas into a liquid) Context(you must remove,List([74, 89))):(you; must remove heat energy to change; a gas; into a liquid)
you must remove,List([74, 89))
you you
must remove must remove heat energy to change
heat energy to change a gas into a liquid
a gas into a liquid