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: Cancer is a disease in which cells divide out of control. 
Sentence2: Cancer is a disease in which cells grow and divide rapidly.
answer:
Cancer


question:
Sentence1: Chordates have a complete digestive system and a closed circulatory system. 
Sentence2: All chordates are vertebrates.
answer:
Chordates


question:
Sentence1: Rivers are dammed to create reservoirs and hydroelectric power. 
Sentence2: A byproduct of hydropower are resevoirs.
answer:

reservoirs