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: Heterotrophs are living things that cannot make their own food. 
Sentence2: food contains organic molecules.
[A]: food


[Q]: Sentence1: healing requires rest. 
Sentence2: Healing and cell regeneration follows.
[A]: healing


[Q]: Sentence1: Marine species live mainly in shallow coastal waters. 
Sentence2: Water species live mainly in shallow coastal waters.
[A]:
coastal


