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: Organisms cluster around hydrothermal vents in the ocean floor. 
Sentence2: vents on the ocean floor are powered by heat.

Output: vents


Input: Consider Input: Sentence1: Most bryophytes are small. 
Sentence2: Most in the same group as mosses are small.

Output: small


Input: Consider Input: Sentence1: Ozone depletion results in higher levels of UV radiation reaching Earth. 
Sentence2: higher levels of UV radiation reach Earth through atmospheric holes.


Output: Earth