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: Parasites are organisms that live off a host. 
Sentence2: roundworms may be free-living or live off a host.
answer:
host


question:
Sentence1: threatening behavior by predators causes a porcupine to extend its quills. 
Sentence2: Fishers are predators that can eat porcupines.
answer:
predators


question:
Sentence1: Eagles are a big bird. 
Sentence2: a beak is used for catching prey by eagles.
answer:

Eagles