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: Nitrogen is found in proteins, nucleic acids, and chlorophyll. 
Sentence2: Nitrogen, as a gas, is colorless, odorless, and a generally inert element.

Output: Nitrogen


Input: Consider Input: Sentence1: Precipitation falls on the windward side of the mountain range. 
Sentence2: Sheep tend to favour the windward side of a paddock.

Output: windward


Input: Consider Input: Sentence1: Corals form large colonies in shallow tropical water. 
Sentence2: Flower-like animals live in shallow tropical water.


Output: shallow