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: hiding can be used for avoiding predators. 
Sentence2: Camouflage is used for avoiding predators.

Ex Output:
avoiding


Ex Input:
Sentence1: Damage is intensified by moisture stress during drought. 
Sentence2: low amounts of rainfall intensify damage during drought.

Ex Output:
Damage


Ex Input:
Sentence1: Wind is air that is moving across the surface of Earth. 
Sentence2: uneven heating of the earth's crust can cause wind.

Ex Output:

Earth