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: if an object is kicked then force is exerted on that object. 
Sentence2: if an object is kicked then a measurement of newtons is exerted on that object.
Example Output: exerted

Example Input: Sentence1: Leaves make food for the plant. 
Sentence2: Some producers have leaves to help use energy and inorganic molecules.
Example Output: Leaves

Example Input: Sentence1: Cancer cells divide more often than normal cells, and grow out of control. 
Sentence2: homeless cells grow out of control.
Example Output:
control