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: a warm front causes cloudy and rainy weather. 
Sentence2: Stratus clouds are associated with a warm front.

Output: front


Input: Consider Input: Sentence1: Genetics is the study and application of principles of inheritance to plants and animals . 
Sentence2: Pedigrees are useful tools for studying Genetics.

Output: Genetics


Input: Consider Input: Sentence1: a pan is used for cooking food by heating food in it on a stove. 
Sentence2: Healthful Meals Eat a grain food at every meal .


Output: food