"at" at end of sentence

[Laurence Horn]

At 8:35 AM -0500 3/22/02, Dennis R. Preston wrote:
>Hardly Midwestern US. I have yet to visit an English-speaking part of
>the world where many prepositions were not left at the ends of
>sentences.

But the "gratuitous 'at'", as the article Drew Danielson cites calls
it, of "where's it at?", is not your run of the mill garden variety
stranded preposition.  Most stranded prepositions could alternatively
be "pied-piped", to use the traditional Haj Rossian lingo:

Who/What were you referring to?
To who(m)/what were you referring?

Which sheep are you sleeping with?
With which sheep are you sleeping?

Which drawer did I leave my false teeth in?
In which drawer did I leave my false teeth?

But such is not the case here:

Where are my false teeth at?
*At where are my false teeth?

So it's not so much that the preposition "at" was left at the end of
the sentence, it's why it was there in the first place.

larry