Quoting John Cowan <[log in to unmask]>:

> Andreas Johansson scripsit:
> > > Do you have constructions in Swedish like "the mayor of Boston's hat"
> > > (standard)
> >
> > That particular one would be "Boston's mayor's hat", but there's parallel
> > examples, say _kungen av Bostons hatt_ "the king of Boston's hat".
> So there are lexical rules about when to use prep-genitive and when to
> use s-genetive?  "Boston's mayor" sounds unnatural in English, but
> no more or less so than "Boston's king" -- probably because the
> relationship is not possessive, and s-gen. is avoided when not
> possessive, except where both a subjective and an objective genitive
> are present, as in "John's adoption of Irene".

There's lexical rules, but they're quite complex - you can also get other
prepositions, and there's plenty of cases where there are possible alternative

F'rinstance, "the king of Boston" and "the peak of the mountain" can be simply
_Bostons kung_ and _bergets topp_, but if you go analytical, they take
different prepositions; _kungen av Boston_ vs _toppen på berget_.

And this in my 'lect. No doubt, others will disagree on particular cases.

> > > or "That umbrella's the young lady I go with's" (colloquial)?
> >
> > Double genitive? Nope. But you could say _den unga damen jag går meds
> > paraply_, lit "the young lady I'm going with's umbrella".
> I misled you: the first "'s" is the verb "is".  I considered fixing this
> for clarity, but decided to leave it alone in the name of authenticity.
> So "the young lady I go with's" is formally parallel to "John's", but
> certainly an extreme case that would be edited out of formal prose.

OK. Pretty much like in Swedish then. Altho _den unga damen jag går ut meds
paraply_ doesn't sound particularly extreme - a bit informal, perhaps.