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: 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.

Output: exerted


Input: Consider Input: Sentence1: dew is formed when water vapor condenses over night. 
Sentence2: dew is formed when cooling  over night.

Output: dew


Input: Consider Input: Sentence1: stalactites are formed by deposition. 
Sentence2: Chrissospilia is a cave with stalagmites and stalactites.


Output: stalactites