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.

Example Input: Sentence1: Viruses contain DNA but not much else. 
Sentence2: viruses contain encoded information but not much else.
Example Output: Viruses

Example Input: Sentence1: a light bulb is used for seeing in the dark. 
Sentence2: Conventional light bulbs generate light by heating a filament.
Example Output: bulb

Example Input: Sentence1: dew is formed when water vapor condenses over night. 
Sentence2: When water vapor condenses overnight, the temperature has reached the dew point.
Example Output:
condenses