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: Blood type is important for medical reasons. 
Sentence2: Type O is important for medical reasons.

Output: important


Input: Consider Input: Sentence1: an earthquake causes the ground to shake. 
Sentence2: A number of buildings in Istanbul also were damaged in the earthquake.

Output: earthquake


Input: Consider Input: Sentence1: vinegar can cause harm to the eyes. 
Sentence2: It is this bacteria which turns alcohol into acetic acid, the main component of vinegar.


Output: vinegar