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: Consider Input: 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. 

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


Input: Consider Input: 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. 

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


Input: Consider Input: Water vapor is in warm air. The warm air cools. The warm air expands. The water vapor in the air condenses. The water vapor forms water droplets or ice crystals. 


Output: water vapor ,water droplets; ice crystals