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: keeping food cold is used for keeping food fresh. 
Sentence2: Keeping food at 40 degrees F or lower is used for keeping food fresh.
[EX A]: food

[EX Q]: Sentence1: Microbes are also called bacteria or microorganisms. 
Sentence2: Disease-causing bacteria have a negative impact on the body.
[EX A]: bacteria

[EX Q]: Sentence1: Pregnancy begins with a fertilized egg. 
Sentence2: pregnancy begins when a sperm and an egg fuse.
[EX A]:
Pregnancy