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: a wildfire changes an ecosystem drastically. 
Sentence2: Forest fires change an ecosystem drastically.

Answer: changes


Question: Sentence1: a camera is used for recording images. 
Sentence2: a camera is used for recording binary.

Answer: camera


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

Answer:
cells