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: Gases cause pressure beneath the earth. The gases come to a head and push molten magma to the surface. The magma cools. With enough time the pressure builds up greatly. The resulting volcano may explode. 
Output:
gases ,pressure ,magma; molten magma ,volcano 