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: Bacteria and Viruses Bacteria and viruses can cause diseases. 
Sentence2: bacteria can have a negative impact on an organism.

A: Bacteria
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Q: Sentence1: the uterus is used in reproduction. 
Sentence2: Reproduction uses the same organ as menstruation.

A: reproduction
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Q: Sentence1: Pedigree A pedigree is a map of the types of hemoglobin in the family tree. 
Sentence2: a map of the types of hemoglobin in the family tree is a useful tool for studying inheritance patterns.

A:
family
****