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: Hermit crabs use the shells of dead snails for homes. 
Sentence2: Hermits crabs use dead snails shells as their place to live.

Answer: Hermit


Question: Sentence1: Amphibians have permeable skin that easily absorbs substances from the environment. 
Sentence2: Some substances are harmful to the body and block biological systems.

Answer: substances


Question: Sentence1: Ozone Ozone is a highly toxic invisible gas. 
Sentence2: a loss of highly toxic invisible gas has created a hole over Antarctica.

Answer:
gas