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: Cells are the units of function in living things. 
Sentence2: living things cannot survive without oxygen.

Answer: living


Question: Sentence1: Clouds are one form of condensation. 
Sentence2: Clouds are one form of changing from a gas into a liquid by reducing heat energy.

Answer: Clouds


Question: Sentence1: intense heat has a negative impact on an organism. 
Sentence2: To have the form of heat is to be-hot.

Answer:
heat