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: Water is essential for all life on Earth. 
Sentence2: H2O is needed for all life on Eartth.

Output: Earth


Input: Consider Input: Sentence1: sharpening an object causes that object to change shape. 
Sentence2: sharpening a knife causes it to change shape.

Output: causes


Input: Consider Input: Sentence1: medicine is used for curing people when they are sick. 
Sentence2: Babies are the MOST inquisitive of people.


Output: people