Sometimes I encounter ain't, but I really don't know how to translate it properly.
What does ain't stand for? If I really wanted to use it, in which contexts would you say it's acceptable using it?
Word Usage – Meaning and Usage of ‘Ain’t’
meaningregisterword-usage
Related Solutions
First of all, let's be clear that ain't is not commonly used in proper and correct speech. It is a word, it is technically correct, and it does take the meaning of "[to be] not", as you have surmised. However it is most often used in uneducated speech, so you must be sure to take everything with a grain of salt when you see it used. I certainly wouldn't suggest you begin using it in formal contexts.
Let's begin with your first assertion:
I ain't an idiot
expands to
I am not an idiot
Which, in my understanding means "Well, I am declaring myself an idiot"
Ain't does indeed expand to am not here, but it certainly doesn't mean that the person thinks they are an idiot. They are quite clearly saying that they are not an idiot (probably in response to someone who has said they are one). I am not [x] is always a claim that a person is not something.
It just ain't done good
expands to
It just have not done good
Which, in my understanding means "An action didn't generated good results of if"
Now we return to my original point that ain't is often used in uneducated speech. The formal way to say this would be "It just is not done well." This means that [x] action (or the result of said action) has not been performed properly. For example, a teacher could be looking at a student's painting in an art class, and comment that the painting was not done (ie. not painted) well. But ain't doesn't expand to have not here, as you suggest; it expands to is not (simply another form of [to be] not).
But I ain't marchin' anymore
expands to
But I am not marching anymore
Which, in my understanding means "I am saying, that I will stop marching"
Your expansion to am not is correct, and you've almost got the interpretation down; what this means is I am no longer marching. I have not been marching for some period time up until this point, and I will continue not to march. The distinction from your interpretation is that they are not saying "I will stop marching from this point forward." They have already stopped marching.
Hey, ain't gonna cry no more today
expands to
Hey, I am not going to cry no more today
This one is a bit weird, but in my understanding means "I am declaring my intentions of crying no more that I already did, today"
Again we return to the issue of uneducated speech; the ain't is actually completely straightforward in this example, it does indeed expand to am not. However you have a different problem which is displayed in uneducated speech; that of the word no used when it ought to be any. This could have been correctly written I ain't going to cry any more today (expanding to I am not going to cry any more today). This means that at some point today they have cried a certain amount, and intend to not cry again for the rest of the day. They will not cry any more (or any longer).
I ain't no quitter
expands to
I am not no quitter
Which, in my understanding means that "I am a quitter", since be first negation negates the second...
This example has the same problem as the last one; the ain't is straight forward but the no is incorrect. It should read I ain't a quitter (expanded to I am not a quitter). Which, similar to your first example where the person professes to not be an idiot, means that the person denies any accusation that they might be a quitter.
So, overall, be careful with ain't. You've got a good handle on the expansion overall, but you have to watch out for the extra no/not negations you might find. Use context to help you as much as possible; rarely would someone claim to be a quitter or an idiot, so your best guess should be that it means the opposite :)
The phrase and all that is strictly informal, because it’s sloppy.
A person says and all that when they know that greater precision is called for but they don’t want to make the effort to find words to describe the category they’re talking about. It’s common and ordinary in everyday, informal speech.
It’s grammatically correct even without a word after that. That functions as a demonstrative pronoun, and all modifies it to mean that you’re regarding that as a whole somewhat carelessly, without regard to details and distinctions.
An informal phrase in a formal context
One reason you find and all that in books is because it occurs in dialogue. Books are normally written in formal English, but they can contain informal English in quotations. In indirect speech, appending and all that can suggest that someone is taking a sloppy, dismissive attitude toward a topic. (In informal contexts, the phrase doesn’t carry the connotation of dismissiveness nearly as often.)
Occasionally, deliberate informality in a formal context makes good rhetoric. For example, there is a textbook on vector calculus titled Div, Grad, Curl, and All That. The title, by using the phrase and all that, suggests that the book will cover the topic informally, in a tone and style that are easier to understand than the very formal approaches more commonly found in math textbooks.
The phrase and all that occasionally appears in book titles or other formal contexts to allude to a parody of English history, 1066 and All That by Sellar and Yeatman, published in 1930. Its premise is that it presents English history as you actually remember it from school. For humor, it mixes things up and reduces people and events to absurd simplicity. For example, the book incorrectly calls Alfred the Great “Alfred the Cake” because of a famous story about the real Alfred and some cakes. It rates nearly every king “a good king” or “a bad king”. The book is well-known enough that people sometimes write and all that to designate an irreverent or false history of another topic, either a deliberate one or the way people have misremembered it.
Formal equivalents
There are equivalent phrases in formal English that also avoid explicitly describing some category, leaving the reader to fill in the details: and the like, and such, and similar things. If you can replace things with a more-precise noun, that’s better in formal English. Another formal choice is et cetera, Latin for “and the rest”, usually abbreviated etc.
You could do a lot with this item, such as writing, drawing, and the like.
You can do a lot with this item, including writing, drawing, and the like.
With this item, you can do writing, drawing, and the like.
I removed your first like to avoid repeating the word.
In this particular example, it’s probably better to avoid the phrase entirely, since like, such as, and including all clearly indicate that the list is not exhaustive:
You can do a lot with this item, including writing and drawing.
That has the clarity and crispness of formal English.
Best Answer
Ain’t is a negative present-tense form of the verbs be and have employed in all persons and numbers:
It represents a coalescence of the ordinary spoken contractions of not and the three relevant forms of the two verbs:
It is used wherever be not is used: as a copula, in progressive constructions, and in passives; and where have not is used as an auxiliary, in perfect constructions.
Ain’t is not slang (which means, roughly, a fairly novel usage employed by an ‘in-group’ as a token of their ‘in-ness’) but a colloquialism which was at one time used virtually universally. You find it very often in 18th- and 19th-century plays and novels, in the mouths of persons of high social standing.
However, it aroused particular hostility among 19th century schoolmarms, who assaulted it ruthlessly and succeeded in painting it as the mark of illiterate speech. Accordingly, it should not be used in formal contexts except as an ironic nod to the vernacular. It is still very common in speech, but regarded as sub-standard rather than merely non-standard.