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: An isotope capable of undergoing fission is called a fissile isotope . 
Sentence2: fissile isotopes are capable of dividing into two parts.

capable