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: Heat and temperature are the same. 
Sentence2: a thermometer is used to measure heat.

Output: Heat


Input: Consider Input: Sentence1: a mutation in the sex cells of a parent can cause a new trait to appear in the parent 's offspring. 
Sentence2: cancer of a parent's cells can cause a new trait to appear in their offspring.

Output: appear


Input: Consider Input: Sentence1: treating water is used to remove harmful substances before drinking. 
Sentence2: Clean drinking water is a luxury.


Output: drinking