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: Protein Protein is needed for tissue maintenance and repair. 
Sentence2: protein repairs cells.
[EX A]: Protein

[EX Q]: Sentence1: Infection is what ultimately leads to death. 
Sentence2: scraping oneself on a contaminated object may cause death.
[EX A]: death

[EX Q]: Sentence1: Large amounts of nitrogen are found naturally in the air and soil, and in living organisms. 
Sentence2: Proteins,nucleic acids and chlorophyll are found naturally in the air and soil, and living organisms.
[EX A]:
air