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.

[EX Q]: Sentence1: Finally, the fluid in the nephron reaches a collecting duct . 
Sentence2: fluid in the kidneys collect into ducts.
[EX A]: fluid

[EX Q]: Sentence1: Refrigerators are major users of electricity. 
Sentence2: Keeping food fresh for a long period of time requires a lot of electricity.
[EX A]: electricity

[EX Q]: Sentence1: lack of moisture in the air causes low amounts of rainfall. 
Sentence2: low moisture in the air can cause plants to die.
[EX A]:
air