TASK DEFINITION: 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. 
PROBLEM: There is a fetus in the womb. They are born and are a baby. The baby grows into a child. Puberty turns the child into an adolescent. The adolescent becomes an adult. An adult becomes an elderly person. The elderly person dies. 

SOLUTION: fetus ,baby ,child ,adolescent ,adult ,elderly person 

PROBLEM: Rain clouds travel across the sky. Rain clouds are stopped or slowed by mountains or wind. The rain clouds drop the rain. The clouds are no longer raining when or if they reach the other side of the obstacle. On the other side of the mountains or rain, there isn't much rain. The area that receives little rain develops a very different ecosystem. The area that receives little rain becomes a desert. 

SOLUTION: rain clouds ,rain ,clouds ,a very different ecosystem ,desert 

PROBLEM: Gather the ingredients for the cake. Mix the flour, sugar, egg, and water to make batter. Pour the mixture into a cake pan. Place the cake in the oven to cook. Take the cake out when it is cooked through. Let the cake cool. Serve the cake. 

SOLUTION:
flour ,sugar ,egg ,water ,batter ,cake