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

A: host
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Q: Sentence1: Aggression is behavior that is intended to cause harm or pain. 
Sentence2: Verbal violence is behavior that is intended to cause harm or pain.

A: behavior
****
Q: Sentence1: ink is used for hiding from predators by octopuses. 
Sentence2: Ink is used for hiding from predators by some animals that eat small crabs.

A:
hiding
****