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: All frogs are amphibians. 
Sentence2: frogs have permeable skin that easily absorbs substances from the environment.

Answer: frogs


Question: Sentence1: Mitosis is cell division. 
Sentence2: mitosis often causes growth.

Answer: Mitosis


Question: Sentence1: breathing is when a gill converts from oxygen in water into oxygen in blood. 
Sentence2: breathing is when a gill converts from oxygen in water into Hemoglobin.

Answer:
breathing