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. 

Q: Bacteria enters the body. Bloodstream. Cells in the body are attacked. Cells are killed. Different kinds of sickness are formed. 

A: bacteria ,cells ,sickness 
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Q: He air we breathe contains oxygen and other gases. Once in the lungs, oxygen is moved into the bloodstream and carried through your body. At each cell in your body, oxygen is exchanged for a waste gas called carbon dioxide. Your bloodstream then carries this waste gas back to the lungs where it is removed from the blood stream and then exhaled. Your lungs and respiratory system automatically perform this vital process, called gas exchange. 

A: air ,oxygen ,carbon dioxide; waste gas 
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Q: A forest fire starts. The fire surrounds the vicinity. The animals are trapped. Those that survive have their habitat destroyed. The survivors must find a new habitat. Conflict with other animals occur. 

A:
forest fire ,animals ,habitat 
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