Definition: 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: Sentence1: Adolescence is a time of significant mental, emotional, and social changes. 
Sentence2: at least one in every five people in the world is in a time of significant mental, emotional and social changes.

changes