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: Oxygen enters the respiratory system through the mouth and the nose. 
Sentence2: Breathing masks are used to keep harmful particles from entering the mouth and the nose.

nose