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.

Example Input: Sentence1: forming coal requires decaying vegetation. 
Sentence2: Forming fossil fuels requires decaying vegetation.
Example Output: decaying

Example Input: Sentence1: a flashlight converts chemical energy into light energy. 
Sentence2: PALight Flashlights are the ultimate personal LED flashlights.
Example Output: flashlight

Example Input: Sentence1: Minerals are chemical elements that are essential for body processes. 
Sentence2: Eggs are loaded with vitamins and minerals.
Example Output:
Minerals