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: DNA is made up of nucleotides. 
Sentence2: Mutations can change the structure of DNA.

Answer: DNA


Question: Sentence1: Climate refers to weather over a long period of time. 
Sentence2: weather is generally described in terms of temperature and moisture.

Answer: long


Question: Sentence1: the moon revolving around the Earth causes the phases of the moon. 
Sentence2: Phases of the Moon are caused by differing amounts of light reflected from the Earth.

Answer:
phases