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: Minerals are chemical elements that are essential for body processes. 
Sentence2: minerals are needed by body processes.

Ex Output:
processes


Ex Input:
Sentence1: Flowers produce seeds for reproduction. 
Sentence2: flowers require dispersal for reproduction.

Ex Output:
Flowers


Ex Input:
Sentence1: Rainbows are very pretty. 
Sentence2: sunlight and rain are pretty.

Ex Output:

pretty