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: mineral graphite is used for making pencil lead. 
Sentence2: Diamond and graphite are made of carbon.

Output: graphite


Input: Consider Input: Sentence1: an animal requires nutrients to grow and heal. 
Sentence2: Microbes can help an animal to grow and heal.

Output: grow


Input: Consider Input: Sentence1: Flooding causes much of the hurricane damage. 
Sentence2: Heavy rains cause much of the hurricane damage.


Output: damage