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.

Input: Consider Input: Sentence1: Genetics is the study of inheritance. 
Sentence2: Pedigrees are useful tools for studying genetics.

Output: Genetics


Input: Consider Input: Sentence1: waxy leaves are used for storing water by some plants. 
Sentence2: waxy leaves are used for water conservation by some plants.

Output: leaves


Input: Consider Input: Sentence1: The human being is self-aware. 
Sentence2: If something that is self-aware disturbs animals in a location then those animals will move to a different location.


Output: self-aware