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. 
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Question: Food is put into mouth. Food is chewed and mixed with saliva (spit). Food travels down the esophagus (throat). Food travels into the stomach. Acid in the stomach breaks the food down further. Food travels into the small intestine. Nutrients from food are absorbed into the blood stream. Food travels into the large intestine. Most of the remaining material is now waste. The waste is eventually removed from the body. 

Answer: food ,saliva;spit ,acid ,nutrients ,waste 


Question: Coal is burned in a boiler. Steam is produced under pressure. Flows into a turbine. The turbine spins. Creates electricity. 

Answer: coal ,steam ,turbine ,electricity 


Question: Warm air rises. Then it expandes and cools. Some of the vapor condenses onto tiny pieces of dust that are floating in the air. Forms a tiny droplet around each dust particle. Billions of these droplets come together they become a visible cloud. 

Answer:
warm air ,vapor ,tiny pieces of dust ; dust particle ,droplet ,cloud