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.

Q: Sentence1: Nitrogen is found in proteins, nucleic acids, and chlorophyll. 
Sentence2: Life without protein is impossible.

A: proteins
****
Q: Sentence1: an animal requires air for survival. 
Sentence2: The Moon has no atmosphere and no air.

A: air
****
Q: Sentence1: Oaks are the most commonly attacked plants. 
Sentence2: Ground tissue makes up most of the interior of an oak.

A:
Oaks
****