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: Balance is the ability to sense and maintain body position. 
Sentence2: Another part of the inner ear is used for balance.

Ex Output:
Balance


Ex Input:
Sentence1: Leaves make food for the plant. 
Sentence2: Some producers have leaves to help use energy and inorganic molecules.

Ex Output:
Leaves


Ex Input:
Sentence1: Weather Clear weather usually means good visibility. 
Sentence2: High pressure systems cause good visibility.

Ex Output:

good