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. 

[EX Q]: Water in the clouds becomes very cold. The cold water forms ice crystals. The ice crystals grow by absorbing surrounding water droplets. Form snowflakes. The snowflakes fall to the ground. 
[EX A]: water ,ice crystals ,snowflakes 

[EX Q]: Water flows by rocks. Chemicals are in the waters. Chemicals react with rocks. Rocks change to a different kind of rock. Oxygen in the air reacts with rocks. Rocks change to a different kind of rock. 
[EX A]: water ,rocks ,chemicals ,oxygen 

[EX Q]: Items are collected. The items are sorted. Trash is removed from everything else. Goes to a landfill. The items go into a baler machine for each kind of material. They come out as bales. The bales are shipped to manufacturers to use to make products. 
[EX A]:
items ,trash ,bales ,products