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: Temperature Scales Temperature is the energy of vibration. 
Sentence2: a thermometer is used to measure energy of vibration.

Answer: energy


Question: Sentence1: Finally, the fluid in the nephron reaches a collecting duct . 
Sentence2: fluid in the kidneys collect into ducts.

Answer: fluid


Question: Sentence1: Mollusks have a circulatory system with one or two hearts that pump blood. 
Sentence2: Blood is pumped by the heart into blood vessels called arteries.

Answer:
pump