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: Electron microscopes use a beam of electrons as their source of illumination. 
Sentence2: Electrons are used to illuminate small objects and make them appear bigger.

illumination