Today, tomorrow and yesterday: no preposition.

Days of the week: preposition 'on', eg: on Tuesday, on Wednesday, etc. (Americans leave out the 'on', however.)

Dates: 'on the' for numbers, eg 'on the 5th of November'

Months: 'In' November, 'on' the 5th of November.

Years: 'In' 1776. On the 24th of August, (in) 1776. 'In' is a bit redundant here, and is usually left out.

Americans use a shorthand version of the above, leaving out many of the prepositions.

I am not quarrelling with Nova (as you say, it is Latin, and I say that is no reason to say "No=wa") but I speak as a Scot when I say that the Scottish version is as I described: Scoh-shia. What you say in the new Canadian one I leave for you to report.
Reminds me of Rhodesia, which everyone pronounced with "Rho-DEEzh-ya" at the end, except my aunt who was a Rhodesian, who called it "Rho-DEEZ-ee-a". Now it's called Zimbabwe, but that's another language, of course.

If you are criticised for leaving words out in what is a well-known and commonly used expression, owing to its being ungrammatical (eg, lacking a subject or a verb), just say it's ellipsis. "Okay?" (= "Is that okay?"). That should put their gas on a peep for a while.
That is why commands or orders don't have subjects: "Stand up!" - who is standing up? It is understood, so left out.

In the examples of phrases using "be" mentioned above, surely we have instances of ellipsis and the employment of the subjunctive because we are talking of things which may or may not be. As in "Be that true", which suggests maybe it is, maybe it isn't. It is short (ellipsis) for "If that is true (and it may not be)".

Makes Japanese seem easy by comparison, doesn't it? [ 'It' is missing from the last sentence, so no subject because I assumed it: I used ellipsis. We all do. Often. Especially in conversational English. Look! There I go again.]

Nova Scotia = New Scotland. Old Scots word for Scotland: Scotia. pronounced SCO-sh-ya with a little "grace note" of a "y" or "i" before the final "a". Like Indonesia, where there is a little sound "y" before the final "a": Indo-NEEZH-ya. Honest, I'm a Scotsman, and I like Bali too.

I really like "hey" and "hi" and all those American terms discussed here. In South Africa we used to call "Howzitt?" in a cheery tone of voice, asking "How is it?", making it quite clear that we didn't want any serious reply, beyond perhaps "Ja" pronounced "Ya" and certainly were not concerned in the least about how the other party fared. I really like that too. But in the depths of rural England I hear an irritating variant: "All right???" meaning "Are you all right?" asked in a serious, worried and concerned tone, sounding as if the questioner suspects that the addressee has gone completely mad. Women entering pubs see friends already ensconced there, stop in their tracks and query : "You all right?" slowly and loudly, the note rising from conversational level to a high interrogative shriek, sounding like serious concern for the well-being of their victims. Actually they don't give a damn.

Stand back, Mediator. He's got him on the ropes. How much of a contest is it?!

Did I say European? I mean exotic - shark's fin is not European. Just picture my embarrassment.

a whole nother story = a-whole-nother story = another story with the emphatic "whole" placed in the middle of the word.

It reminds me of the Londoner landlord of a pub I once knew well who punctuated every phrase with the colourful "bleedin'" (="bleeding" from "by my lady" ref. to Virgin Mary - a medieval cuss word). Introducing interesting European menus to what was on offer
(this was the 80s) he told his customers to try the Greek one, and shark's fin soup too: "we've got bleedin' Jaws on the menu tonight, mate, bleedin' Jaws. And what's more, taramableedinsalata".

But all that's a whole nother story.

Now there's a bit of a thing!

Okay, that's enough from me on finding examples of "of a". The rest is silence. Maybe.

Accusations of petty snobbery ...!

I see one hell (or American: heck) of a quarrel developing here, or am I just being hopeful?