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: Centrioles come in pairs. 
Sentence2: Something that comes in pairs are organelles involved in cell division.

Answer: come


Question: Sentence1: microbial fuel cells convert chemical energy into electrical energy. 
Sentence2: microbial fuel cells convert chemical energy into kinetic energy.

Answer: cells


Question: Sentence1: igneous rocks are formed from magma cooling. 
Sentence2: Igneous rocks are formed by the solidification of magma.

Answer:
igneous