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. 

Example Input: Grass and small plants grow in an area. These plants die. The soil gains organic material. The soil becomes more fertile. Larger plants are able to be supported. Trees eventually grow. 
Example Output: Grass ,Small plants ,organic material ,larger plants ,trees 

Example Input: Coal is burned in a boiler. Steam is produced under pressure. Flows into a turbine. The turbine spins. Creates electricity. 
Example Output: coal ,steam ,turbine ,electricity 

Example Input: A butterfly starts as an egg. The egg hatches. A larva emerges. The larva eats and grows. The larva sheds its skin. The larva enters a chrysalis. The pupa grows inside the chrysalis. The adult butterfly exits the chrysalis. The adult butterfly is now fully grown. The adult butterfly lays more eggs. 
Example Output:
egg ; eggs ,larva ,pupa ,adult butterfly 

