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.

[Q]: Sentence1: a battery converts chemical energy into electrical energy. 
Sentence2: Battery electricity comes conversion.
[A]: battery


[Q]: Sentence1: Amphibians have permeable skin that easily absorbs substances from the environment. 
Sentence2: permeable skin easily absorbs air to breathe through.
[A]: absorbs


[Q]: Sentence1: Root hairs are thin-walled extensions of the epidermal cells in roots. 
Sentence2: Most plants grow epidermal cells down into the soil to absorb water and minerals.
[A]:
cells