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From Conservapedia

"Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo" is one of the longest, if not the longest, sentences using only one homophone. In this case, buffalo means the city, the animal, and the verb meaning to overawe or intimidate. Replacing "buffalo" meaning animal with "person" and the buffalo verb with "intimidate," "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo" can be translated as "Buffalo people [that] Buffalo people intimidate [also] intimidate Buffalo people," or "People from Buffalo, who are intimidated by people from Buffalo, intimidate people from Buffalo."