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: Hair helps to insulate and protect the body. 
Sentence2: most mammals have insulation that also protects the body.

Output: body


Input: Consider Input: Sentence1: Metabolic rate is the rate at which food is burned for energy. 
Sentence2: thyroid hormones increase the rate of energy consumption.

Output: energy


Input: Consider Input: Sentence1: Some viruses live in a dormant state inside the body. 
Sentence2: When inactive or dormant, Dendrobiums require little or no fertilizer.


Output: dormant