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: All light is energy, which is eventually absorbed and turned into heat. 
Sentence2: Light energy causes objects to warm up.

energy