Instructions: 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. 
Input: A nuclear reactor generates heat by nuclear fission. The heat created raises steam. The steam runs through turbines. The turbines generate electricity. The electricity leaves the station. 
Output:
heat ,steam ,electricity 