Contractions

A contraction is a shortened version of the written and spoken forms of a word, syllable, or word group, created by omission of internal letters. In traditional grammar, contraction can denote the formation of a new word from one word or a group of words, for example, by elision. This often occurs in rendering a common sequence of words or, as in French, in maintaining a flowing sound. In linguistic analysis, contractions should not be confused with abbreviations or acronyms (including initialisms), with which they share some semantic and phonetic functions, though all three are connoted by the term "abbreviation" in loose parlance. Contraction is also distinguished from clipping, where beginnings and endings are omitted.

English contractions

English has a number of contractions, mostly involving the elision of a vowel (which is replaced by an apostrophe in writing), as in I'm for "I am", and sometimes other changes as well, as in won't for "will not". These contractions are commonly used in speech and in informal writing, though tend to be avoided in more formal writing.

The main contractions are listed in the following table (for more explanation see English auxiliaries and contractions).

Full form	Contracted	Notes
not	–n't	Irregular forms: "ain't", "don't", "won't", "shan't". "n't" can only be attached to an auxiliary verb which is itself not contracted.
let us	let's
I am	I'm
are	–'re	we're /wɪr/ is pronounced differently than were /wɜr/ in some dialects.
is	–'s
does		very informal, as in "What's he do there every day?"
has
have	–'ve
had	–'d
did		very informal, as in "Where'd she go?"
would
will	–'ll
of	o'–	used mostly in o'clock, where it is mandatory in contemporary use
it	't–	Archaic, except in stock uses such as 'Twas the night before Christmas
them	'em	Perceived as informal, yet old. Actually from hem, which is not the same word as them, a Norse loan.
is not	isn't, or ain't	ain't is contracted from am not and more recently is not; it is generally considered a colloquial contraction.