Most contractions in English are pretty straightforward. The pattern of contraction for verbs and the negative adverb ‘not‘ is very basic in majority instances. You first write the contraction, then the n of not, then an apostrophe, followed by the t of not. This is true for all of the following examples:
is not, isn’t;
are not, aren’t;
was not, wasn’t;
were not, weren’t;
has not, hasn’t;
have not, haven’t;
had not, hadn’t;
could not, couldn’t;
do not, don’t;
does not, doesn’t;
did not, didn’t;
may not, mayn’t;
might not, mightn’t;
should not, shouldn’t;
would not, wouldn’t;
must not, mustn’t;
ought not, oughtn’t;
dare not, daren’t;
need not, needn’t.
There are only three of the most frequently used verb + negative adverb examples that don’t work like this: shan’t, ain’t and won’t. Let’s look at how they differ from the majority of examples and then try to understand why.
Shan’t is the contraction of shall not, ain’t is a contraction of am not and won’t is defined as the contraction of will not. Look at what happens when we add the negative adverb to each one:
shall + not (take away ll; take away o) —> shan’t
Now, you may wonder why aren’t there two apostrophes, since two letters are removed in one place and one in another place? Why isn’t it sha’n’t? The fact is that at one time as recently as the 20th Century, it was spelled as sha’n’t! Perhaps people who didn’t understand the role of the apostrophe “misspelled” it or brought it into line by copying the pattern of the majority of verb/negative adverb contractions.
In a similar way, am not was also spelled as amn’t instead of ain’t which later came into use.
Ain’t is a contraction for am not, is not, are not, has not, and have not in the common English language vernacular. In some dialects ain’t is also used as a contraction of do not, does not, and did not. The development of ain’t for the various forms of to be not, to have not, and to do not occurred independently, at different times. The usage of ain’t for the forms of to be not was established by the mid-18th century, and for the forms of to have not by the early 19th century.
The usage of ain’t is a perennial subject of controversy in English. Ain’t is commonly used by many speakers in oral or informal settings, especially in certain regions and dialects. Its usage is often highly stigmatized, and it may be used as a marker of socio-economic or regional status or education level. Its use is generally considered non-standard by dictionaries and style guides except when used for rhetorical effect, and it is rarely found in formal written works.
Amn’t as a contraction of am not is known from 1618. As the “mn” combination of two nasal consonants is disfavoured by many English speakers, the “m” of amn’t began to be elided, reflected in writing with the new form an’t. Aren’t as a contraction for are not first appeared in 1675. In non-rhotic dialects, aren’t lost its “r” sound, and began to be pronounced as an’t. An’t (sometimes a’n’t) arose from am not and are not almost simultaneously.
I am doing good, am I not?
–>I am doing good, amn’t I? (Earlier Usage)
–>I am doing good, ain’t I? (Present day usage)
What about won’t?
will + not (take away ll; take away o) —> win’t rather than won’t
The fact is that the contraction won’t was created when an older form of will not was in use. At different times and places “will” came out as wulle, wole, wool, welle, wel, wile, wyll, and even ull, and ool. From at least the 16th century, the preferred form was wonnot from “woll not,” with occasional departures later to winnot, wunnot, or the expected willn’t. Finally after years of change by our linguistic ancestors, “will” won the battle of the “woles/wulles/ools,” but for the negative contraction, “wonnot” simply won out, and contracted further to the “won’t” we use today. According to the Oxford English Dictionary, won’t was formed from woll not, an earlier form of will not. Knowing this, we can now set up our diagram of the formation of the contraction like this:
woll + not (take away ll; take away o) —> won’t
And we can see that it is formed identically to shan’t. So did won’t at one time have a double apostrophe as well? Yes: at one time, the correct spelling (or a correct spelling) was wo’n’t!
The verb “will” has been spelled all sorts of ways since first showing up as wyllan around 1,000 in Aelfric’sGrammar, an Old English introduction to Latin grammar. The Oxford English Dictionary has many Middle English examples of the wole or wol spelling dating back to the 1200s.