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.

Ex Input:
Sentence1: Aquatic animals are adapted to living within certain salinity ranges. 
Sentence2: Animals adapted to living within certain salinity ranges require great amounts of water to survive.

Ex Output:
adapted


Ex Input:
Sentence1: Basically the process is pretty simple. 
Sentence2: All cells share some of the same structures and simple processes.

Ex Output:
process


Ex Input:
Sentence1: Sponges are a source of food for many species of fish. 
Sentence2: Sessile organisms can be a source of food for many species of fish.

Ex Output:

fish