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: Ice Age Ice ages occur during times known as glacial epochs. 
Sentence2: When the planet was buried in snow and ice it was known as the glacial epochs.

glacial