Can you define this grammatically?
He has a lot of money.
He has a lot of money.
A lot of
"A lot," I believe, is a determiner like "five" or "the" but it may be an adjective... I can't decide. The reason for the word "of" is because "a lot" (I'm assuming) used to be followed by a noun in the genitive case (numbers did the same thing to nouns in Old English) and "of" is similar to a prefix of the genitive case in this sense... Just like "because of" or "instead of" (just as they are in German, "wegen" and "instatt" take the genitive case).
"A lot of" (as well as "lots of") cannot be a determiner because one can say things like "a lot of the people", and multiple determiners for a given noun are forbidden in English in general. Also, they clearly do not function as prepositions, unlike forms like "because of" and "instead of". Yet at the same time, I am rather inclined to treat "a lot of" and "lots of" as something more than just a plain noun (with or without a determiner) connected to another noun with "of", as its function seems to be relatively grammaticalized in English dialects today. One way or another, they seem to fit in with many similar semi-grammaticalized constructions in English where an abstract noun that refers to some quantity, mass, or type of something is connected with an actual concrete noun with "of".
A 'lot' is an old measurement (a very large one at that) of salt. If you had a lot of salt, it would mean you had vast amounts of salt.
This has changed to mean vast amounts of anything.
Lot can also refer to a medium sized group of people (usually 5-20 people)
Our grad students are a good lot.
This lot's been skipping class lately.
''How dark is it'' Dark
is more logical than ''How dark is it'' Tanned.
It's stupid to repeat what they asked you. It's more logical to provide units to quantify how many there are/how dark something is.
I would say "a lot of" is a fixed phrase grammatically employed as an quantitative adjective: I have 'a lot of' money. How much money? "A lot"
but technically, it is an 'indef. article' + 'noun' + 'ablative preposition'
Even though it corresponds coincidentally to how German uses a genitive, here, "a lot of money" doesn't = "money's lot" (i.e. the lot belongs to, or is the property of money), it's "a lot [deal, amount] of [from] money" --ablative.