In this task, you are given a paragraph, and your job is to generate comma-separated entities present in the given paragraph. Generate entities from a given passage in such a way that (i) they are present in the paragraph, (ii) they are non-duplicate, (iii) they underwent a state change during the process. Avoid creating entities that (i) aren't present in the process paragraph and (ii) aren't significant. 
One example is below.
Q:  Magma rises from deep in the earth. The magma goes into volcanos. The volcanos pressure the magma upwards. The pressure causes the magma to push through the surface of the volcano. The lava cools. The lava forms new rock. New magma is pressured to the surface of the volcano. The volcano bursts through the rock the formed after the last eruption. 
A:  magma ,lava ,new rock 
Rationale: The entities are present in the process paragraph and they undergo state change. So, this is a positive example.
Q: Air contains invisible moisture called water vapor. Excess water vapor is condensed out as water in the form of water droplets. Water droplets are carried up into the clouds. The clouds become heavy with water droplets. When the cloud is saturated. Rain will fall. 
A:
water vapor ,water droplets ,cloud ,rain 