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: if an object in a fluid is more dense than that fluid then that object will sink in that fluid because of gravity. 
Sentence2: Most seeds are more dense than water.

Answer: dense


Question: Sentence1: Animals behave in a variety of ways which enhance their chances of survival and reproduction. 
Sentence2: Animals learn to behave to increase chances of survival.

Answer: behave


Question: Sentence1: Nerve impulses are electrical in nature. 
Sentence2: Nerve impulses are received by the dendrites.

Answer:
Nerve