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: Consider Input: Sentence1: Combustion generates toxic fumes. 
Sentence2: High temperatures can cause toxic fumes.

Output: fumes


Input: Consider Input: Sentence1: Antibodies are large, Y-shaped proteins that recognize and bind to antigens. 
Sentence2: Some of the antibodies, antophospholipid antibodies, cause blood clots.

Output: Antibodies


Input: Consider Input: Sentence1: if soil is permeable then water easily flows through that soil. 
Sentence2: If a soil has high permeability, water flows through the soil more freely and may cause chemicals to leach.


Output: flows