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: exercise increases a body 's strength. 
Sentence2: Exercise is more than running and lifting.

Output: exercise


Input: Consider Input: Sentence1: wind is used for producing electricity. 
Sentence2: Winds are caused by pressure differences.

Output: wind


Input: Consider Input: Sentence1: Pressure is sensed by very fine deflections of a sensing diaphragm. 
Sentence2: Touch is the ability to sense very fine defelections of a sensing diaphragm.


Output: diaphragm