However, it's worth noting that "vocabulary" is often used as a collective noun, meaning it refers to a group of words as a whole. In this case, it doesn't typically take a plural form. For example, you might say:
* "The vocabulary of Shakespeare is vast."
* "She has a wide vocabulary."
But you could also say:
* "He studied different vocabularies of different languages." (referring to multiple sets of words)
* "The book includes a list of vocabularies for each chapter." (referring to multiple lists of words)