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: Basically the process is pretty simple. 
Sentence2: All cells share some of the same structures and simple processes.

Output: process


Input: Consider Input: Sentence1: creating wood-free paper does not require cutting down trees. 
Sentence2: creating printed media requires cutting down trees.

Output: creating


Input: Consider Input: Sentence1: Softer melt point wax is used to produce an even burning candle. 
Sentence2: Heat allows candles to burn and wax to melt.


Output: burning