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. 

[Q]: Water gets caught in winds that are moving upward. The water freezes. The water starts to fall. The winds are strong enough from keeping it from falling back to earth. This pattern of rising and falling continues. The hail becomes too large to be pushed up by the wind. The hail finally falls to the ground. 
[A]: water ,hail 


[Q]: Something happens to produce a sound. The sound travels in waves. The sound waves hit an object. The object absorbs some of the sound waves. Some of the sound waves bounce off of the object. The reflected sound waves can be heard, though they have slightly different properties than the original sound. The sound continues to bounce off of things and produce echoes until it is totally absorbed or dissipated. 
[A]: sound ; sound waves ,echoes 


[Q]: Waters flows downwards thanks to gravity. Enters the dam at high pressure. The moving water spins the turbines in the power plant. The turbines turn the generators. The generators spin, and produce electricity. The water leaves the dam at the bottom. 
[A]:
waters;water ,turbines ,generators ,electricity