“420” is stoner slang for “hey, let’s go blaze up, wastiod”, which means that signs that have that mileage number on them tend to get stolen, especially in states that have legalized recreational use. States have dealt with the problem by replacing the signs/mileposts with something that lacks the desired number.
Thank you. I knew you would be good at explaining it. I’m a boomer, we invented wasted. I have no excuse.
Enjoy the chocolates-could come in handy for the munchies. I should warn you though, the weigh station a few miles East on I80 usually has a State Trooper K-9 unit with a drug dog stationed there, so contain your excitement as you exit for the chocolate factory.
In current British currency the main unit is the Pound which is divided into 100 new-pence, now commonly referred to as just “pence”.
Prior to 1971 the Pound was not divided into 100 sub-units. Instead a Pound was divided into 20 smaller units called shillings. Each shilling was further divided into 12 pence.
Note this is not about the denomination of the various coins. It’s about the actual units of account.
So a British cash register of the era would handle things like 2 items at 7 pence each isn’t 14 pence. It’s 1 shilling, 2 pence. Calling that total 14 pence is as illogical / wrong as calling US$1.14 “one hundred and fourteen cents”; mathematically it’s accurate, but as an expression of currency units it’s wrong / nonstandard.
See wiki for more.
Even better - the Roman legions had about 80 men per “century.” (Structure of the Legion | Strategy & Tactics | The Roman Military)
OK, I have one: the proper use of the subjunctive mood. Don’t laugh! I’ll be the first to admit that I probably get it wrong much of the time myself. And that sometimes it is characteristic of very formal, or old-fashioned, or American language. The problem is that, on one hand, it does affect the meaning, but on the other hand some style guides apparently say it does not exist, because reading e.g. BBC News I will quite often run across a sentence that uses the indicative where the subjunctive is clearly called for.
To make up an example,
- It is important that you are alert during the meeting
vs
- It is important that you be alert during the meeting.
Another example (from a textbook): It is appropriate that this tax be abolished. (Vs It is appropriate that this tax is abolished.)
I wish I remembered some of the BBC examples, because the mood made a bigger difference than the above sentences suggest.
In my mind, the two sentences mean very different things. Same with the second set of example sentences.
Oh my god, I just realized, is this thread slowly getting back to the original topic? It was a complete train wreck at one point.
Yes.
Yes. 
Not that I can help with the formal discussion of subjunctive, indicative, preterative, etc. I knows it when I sees it; sorta.
But there is a huge difference between asserting that something ought to happen in the future versus that it is happening now / just happened.
If we can’t reliably communicate that distinction with grammatical mood, then we just need to use a lot more little words. Which is IMO the biggest failing of my own writing; too many words.
I would offer that the “different meanings” are similar to the different meanings of
- I can’t get no satisfaction.
vs
- I can’t get satisfaction.
Which is to say, they technically mean different things (in this case, they’re actually opposites) but habitual use of the former has endowed it with the same meaning in colloquial English as the latter.
In the same way, the “… you are alert” construction is wrong if it’s supposed to mean that you should be alert in the meeting that is coming up, and “appropriate that this tax is abolished” technically implies approval of the fact that the tax is already abolished, whereas “…be abolished” is a call for its abolition. However, context and common usage endows the two forms with the same meaning, namely the subjunctive one despite the use of the indicative. In practical everyday English, the indicative mood would be communicated by completely rephrasing the sentence – e.g.- “I see that you’re alert in this meeting, and I thank you for that” or “I appreciate that the councilors have abolished the tax, which I believe was appropriate”.
I think this kinda usage illustrates the origins of the problem ranted-upon in the OP. The speech-based “-a” ending leads to confusion when converting into letters. “Coulda”, “oughta” and “kinda, sorta” all reflect different constructions, the last one there the likely primary culprit that led to “could of”.
It doesn’t count when it’s intentional. 
What irks me is when someone writes “could of”, “would of” etc. under the serious misapprehension that it’s English.
I don’t think it’s the speech-based -a ending that causes confusion – it’s the speech-based -'ve contraction that leads to the error. In my dialect, 've and of are pronounced exactly the same. I consider would of/could of/should of to be errors of transcription. They’re more orthographical errors than grammatical errors to me (though when written as could of, they clearly are also grammatical errors. That same sentence spoken, though, would not register as an error, which is why I consider it an error more in spelling than anything else.) I’ve seen perfectly literate people make this error when typing/texting spontaneously. I don’t think I’ve ever made this error myself, but I wouldn’t be surprised if I had, as I’ve made much stupider errors when going from brain to fingers.
The poster who made the error that led to this thread has done it again, despite his post here. It must be a hard habit to break when it sounds the same to your ears.
In this thread on breakfast for dinner, it slipped out again twice in his post #11:
Do you ever eat bacon and eggs for dinner? .
The difference is that literate people would find the error on a quick proofread, or would do a facepalm if it was pointed out to them. They are not under the misapprehension that it’s actually English.
I’m legitimately curious about this. Are “could of” and “could’ve” not homophonous in most dialects?
I was agreeing with that. Actually, I don’t really believe it. I was striving to come up with any reason why someone would continue to butcher the words just a couple of days after he explained it even looked terrible to himself.
At least in my dialect (Californian w a later layer of Midwest) the IPA would read as very close, but the pacing is very different as is the relative stress. I don’t tend to run words together.
In my dialect “Could of” sounds like “cood{pause}uhv” all at one stress whereas “could’ve” sounds like “COOD{schwa}v”. The difference is subtle, but it’s real.
Damnit. I just realized a glaring omission in my OP that should have (
) been clarified. Pointed out by many of you afterwards.
I was referring to the written “should of” when a person means should’ve.
Unless someone is speaking very distinctly I don’t know anybody who speaks it without sounding like “should of”. Anywhere in the US anyway.
The crux of the OP wasn’t how it’s said. It’s that so many don’t know that it’s “have” instead of “of”. We all know what’s meant by “could of”. But damnit if you’re going to type or write something understand the words you’re using.
Geez I’m turning into the cranky old man. Now get off my lawn.
BTW, I’m as guilty in this in speech as anyone. If I’m speaking too fast I can sometimes elide the D and say “shoulve” or “coulnt”. Saves me an apostrophe and sometimes I have more important shit to do.
It didn’t “slip out”. That poster has chosen to not give a fuck. If I was an SDMB mod I would be handing out warnings, because it is deliberate trolling.
They are not. Where I come from, many things are not homophones even though I have had teachers insist to me that they are (won & one, for example). Among the differences, “could’ve” is still pretty much one syllable. It’s an elongated syllable, but it’s one. “Could of” is two syllables.
Additionally, I think even though we are not in the East End of London, there are still places in the US where the H is more of less aspirant. If you come from a dialect where it is strongly aspirant, you are less likely to think “could have” sounds like “could of.”
Then, there is the flat A that marks some US dialects, and makes the A in “have” quite distinct from the O in “of.” In those dialects, further, “of” tends to be more like “uhv.” Other dialects use rounder vowels in both words, causing them to sound more alike.
The first time I ever saw anyone make the written mistake “could/would/should of,” I was floored that anyone thought “of” and “have” sounded alike in the slightest bit.
But in some dialects, “of” and “have” do sound very much alike.