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: Sound vibrations can be compared to pond ripples. 
Sentence2: dropping an object into water causes pond ripples.

Answer: pond


Question: Sentence1: Asbestos is a dangerous carcinogen. 
Sentence2: Asbestos causes cancer.

Answer: Asbestos


Question: Sentence1: the digestive system breaks food into nutrients for the body. 
Sentence2: The pancreas is an organ that is part of our digestive system.

Answer:
digestive