There are some cases in English where contractions can't be used. For example, "that's not the kind of person he's." "He is" cannot be contracted into "he's" in this case.
I want to know the rules behind it… but the only information I've found on the Internet so far is "don't use contractions in formal writing" which is far from what I'm asking.
Posted Apr 25, 2012, 9:20 PM UTC
Different contractions have different rules. Are you asking about cliticized be, have, and will/would, or about cliticized n't? For the latter, some restrictions are:
n't follows the modal verb
n't can't follow another contraction (*I'dn't done that)
n't can't appear in a past infinitive (*to haven't asked)
n't can't appear with an auxiliary that is preceded by a modal (**would the police haven't been informed?*)
For the former,
you don't find contractions in clause-final position, as in your example
you don't find contractions on the modal in modal-initial sentences (e.g. **Could've you been there?*)
(Note that in AAVE, these same restriction apply to copula, iirc.)
For both types, never use contractions when the contracted morpheme needs to bear stress.
Most of this comes from Zwicky & Pullum (1983) Warning: PDF.
Zwicky and Pullum (1983) is one of the all time classic linguistics papers, so it's well worth reading, but the TL;DR version is: contractions aren't all one thing grammatically, because n't is actually verb conjugation while 's, 're, 've and 'd aren't.
True. I would have mentioned that except it seemed that OP was more interested in the data than the theory.
The NP-Host Constraint: Auxiliaries may only cliticize onto an NP.
-Kaisse (1983)
That explains why these are bad:
* Not [even in New York]'s John considered easy.
* Not [for a minute]'s he been happy here.
* [That John finally ate]'s making momma happy.
* [That we eat a lot]'s been making her miserable.
Another rule:
If at any point in the syntax, a constituent immediately following be is deleted, then ... be cannot undergo contraction.
-Lakoff (1970)
Wh-movement
* I wonder where the party's [e] tonight.
* I wonder where John's [e].
* I wonder who that man's [e].
Null VP
* You're leaving and he's [e] too.
* Either John's left or Bill's [e].
Comparative Subdeletion
* There are more researchers than they're [e] teachers.
* The table's longer than it's [e] wide.
Heavy NP Shift
* John's [e] to Mary the best friend in the world.
* Mary's [e] after Jane the best athlete on the team.
Distributed Nominalization
* The decision's [e] to go ahead with it.
* Mary's picture's [e] of John in Shirley in Mahopac.
-Examples from Kaisse.
* John's, I think, eaten dinner already.
* John's, Bill said, an excellent writer.
* John's, to my knowledge, a good doctor.
This is just the bit I felt like writing up. But really read Kaisse (1983). Linguists often call this "AR" short for "Auxiliary Reduction," by the way.
I saw your post on r/grammar.
From the notes from a recent lecture I gave: contraction of the verb to be can not occur in an "exposed" position such as at the end of a sentence.
*Yes, I'm.
*Don't tell me you're.
Interestingly, AAE does not allow copula deletion in these positions. IOW, in AAE the copula can only be deleted in positions where Standard American English allows a contraction. Both the SAE rule and the AAE rule are based upon the same principle: reduction in unstressed positions.