Definition: 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: Sentence1: Allergies are a reaction of the immune system to harmful particles in the air. 
Sentence2: A breathing mask can prevent an allergic reaction.

Allergies