instruction:
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.
question:
Sentence1: an animal requires air for survival. 
Sentence2: The Moon has no atmosphere and no air.
answer:
air


question:
Sentence1: Information on DNA is organized into genes. 
Sentence2: DNA codes for proteins.
answer:
DNA


question:
Sentence1: a mutation in the sex cells of a parent can cause a new trait to appear in the parent 's offspring. 
Sentence2: cancer of a parent's cells can cause a new trait to appear in their offspring.
answer:

appear