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.

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.
family

Sentence1: An electric current is a flow of electric charge. 
Sentence2: a magnet moving in a coil of copper wire can cause a flow of electric charge.
charge

Sentence1: Ribosomes are sites where proteins are made. 
Sentence2: ribosomes have RNA.

Ribosomes

