When water vapor cools, it forms clouds (condensation) which become heavy with water and rains back to earth (precipitation).
(it; forms; clouds (condensation) which become heavy with water and rains back to earth (precipitation); T:When water vapor cools) (clouds; become back; heavy with water and rains)
it clouds
forms become back
clouds (condensation) which become heavy with water and rains back to earth (precipitation) T:When water vapor cools
heavy with water and rains