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: bacteria cause food to spoil. 
Sentence2: Food poisoning occurs when spoiled food is eaten.
Example Output: spoil

Example Input: Sentence1: Earthquakes cause massive damage. 
Sentence2: tectonic plates being pushed together causes massive damage.
Example Output: damage

Example Input: Sentence1: Most precipitation occurs as rainfall. 
Sentence2: lack of moisture in the air causes low amounts of precipitation.
Example Output:
precipitation