Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.
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Question: Sentence1: Interstellar space contains a plasma. 
Sentence2: interstellar space contains electrons, atoms, and stars.

Answer: Interstellar


Question: Sentence1: Here, the lungs supply the blood with oxygen. 
Sentence2: Brain cells die quickly if their blood supply is cut off.

Answer: blood


Question: Sentence1: Green plants are producers . 
Sentence2: Green plants are organisms that make food for themselves and other organisms.

Answer:
Green