Clouds and fog form when the temperature of the air reaches the condensation point, which is the point at which water vapor (which is an invisible gas) becomes a liquid.
(the temperature of the air; reaches; the condensation point, which is the point) (the condensation point; is; the point at which water vapor (which is an invisible gas)) (the point; is; an invisible gas)
the temperature of the air the condensation point the point
reaches is is
the condensation point, which is the point
the point at which water vapor (which is an invisible gas)
an invisible gas