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: Most soil nutrients are cations. 
Sentence2: decomposition increases the amount of cations in the soil.

Ex Output:
cations


Ex Input:
Sentence1: when a gas in an open container evaporates , that gas spreads out into the air. 
Sentence2: when a gas in an open container evaporates gas molecules slamming into one another.

Ex Output:
container


Ex Input:
Sentence1: Insulin is a hormone that helps cells absorb sugar from the blood. 
Sentence2: Insulin and glucagon are produced by the pancreas.

Ex Output:

Insulin