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.

[EX Q]: Sentence1: Mollusks live in most terrestrial, freshwater, and marine habitats. 
Sentence2: Clams live in freshwater habitats.
[EX A]: freshwater

[EX Q]: Sentence1: microbial fuel cells convert chemical energy into electrical energy. 
Sentence2: microbial fuel cells convert chemical energy into kinetic energy.
[EX A]: cells

[EX Q]: Sentence1: Cars and busses are both examples of vehicles. 
Sentence2: Cars and busses are used for transportation.
[EX A]:
Cars