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: During winter, the earth in the Northern Hemisphere is tilted away from the sun. 
Sentence2: Winter is caused from being tilted away from the sun and receiving less energy.

winter