English grammar rule Many nn
A quantifier answers the question how much or how many. There are several ways to do this: numbers (two, 144), adjectives (all, several), prepositions (among, between), and pronouns (these, those) answer the question simply. There are also other nouns that answer the questions with prepositional phrases (plenty of, a lot of, one of). Keep in mind that countable nouns require you to use a plural quantifier.
Examples of 'Many nn' rule
Incorrect We took both cat because they got along well. Correct We took both cats because they got along well. Incorrect Jim has taken many flight. Correct Jim has taken many flights.