they may have the same cardinality, but one infinite sentence is obviously longer than the other infinite sentence.

on edit: noting depends on if we consider as elements the words, or the letters.

If one of them, presumably the buffalo sentence, indeed has more letters, then could you give us a invertible scheme that maps to each letter of the police sentence, a letter in the buffalo sentence, that covers all the letters in the police sentence, but has letters in the buffalo sentence still left over.