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: Flowers produce seeds for reproduction. 
Sentence2: flowers require dispersal for reproduction.

Output: Flowers


Input: Consider Input: Sentence1: Most major Atlantic hurricanes start as small disturbances moving westward off Africa. 
Sentence2: When something that starts as a small disturbance moving westward off Africa then moves over land, it will decrease in strength.

Output: Africa


Input: Consider Input: Sentence1: a mutation in the sex cells of a parent can cause a new trait to appear in the parent 's offspring. 
Sentence2: Alleles arise by mutation.


Output: mutation