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: howling is used to warn other wolves by wolves. 
Sentence2: And somewhere a beagle howls a most pitiful sound.
Output:
howling