use(d) to

[Herbert Stahlke]

I've heard "used to" with modals in Indiana.

You must/might/may used to have lived in the South.

sounds okay, and I've heard things like it around here.  Maybe the
etymological final coronal stop is no longer perceived as a preterite and is
interpreted rather as the /t/ of the infinitive marker, making it the base
form "use to".

Too bad you're not running for gov, no matter what they do with the alphabet
out there.

Herb

Arnold writes:

this verb "use(d)" has a very strange syntax.  with one exception, it
behaves just like an extremely defective main verb, a verb that has
only one, finite, form, the past.  (in particular, it lacks a base
form, and so can't occur with infinitival "to" - "*You ought to used
to eat sushi" 'It ought to be the case that you used to eat sushi' -
or modals - "*You must used to eat sushi" 'It must be the case that
you used to eat sushi'.)  the exception is that in negated clauses, in
inversion, and under emphasis, this verb occurs with one, and only
one, auxiliary, supportive "do" (in its past form "did"): "You didn't
use(d) to eat sushi", "Did you use(d) to eat sushi?", "You DID use(d)
to eat sushi"; this is extraordinary, in that supportive "do" is
universally said to require the base form of its complement, and we've
just seen that "use(d)" doesn't (otherwise) *have* a base form.
so, i'm cool on the spelling.  but making sense of the odd
distribution of "use(d)" is quite a nice little puzzle.