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: plant reproduction requires pollination. 
Sentence2: Plant reproduction requires insects and hummingbirds.
answer:
plant


question:
Sentence1: Bird eggs have hard, calcium carbonate shells. 
Sentence2: The reproductive cells of a bird is a hard, calcium carbonate shell.
answer:
calcium


question:
Sentence1: Molecules of DNA are encoded with instructions that tell cells what to do. 
Sentence2: DNA DNA DNA is a person's genetic fingerprint.
answer:

DNA