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 Input:
Sentence1: Absorption of nutrients occurs mainly in the small intestine. 
Sentence2: The small intestine is the main place where food absorption occurs.

Ex Output:
intestine


Ex Input:
Sentence1: protein is used to repair cells by the human body. 
Sentence2: Meat, fish and chicken are rich sources of protein.

Ex Output:
protein


Ex Input:
Sentence1: Plumbing is sometimes damaged during an earthquake. 
Sentence2: Tectonic plates being pushed together can damage plumbing.

Ex Output:

Plumbing