Apostrophes

[Sam172]

Is a single boss owning a single cap:

The boss's cap

or

The boss' cap

?

=)

[Quizmonster]

Boss's. Some words/names ending in 's' do avoid the final 's', however. For example, you will often see "Jesus' miracles" rather than "Jesus's miracles" largely because the latter version has got just too many 's' sounds! You might also see it in "Keats' poetry" rather than "Keats's poetry". I have never seen the final 's' omitted with the word 'boss'.

[Sam172]

Thankyou. I thought it would be that, just I wasn't quite sure.

[Peter Pedant]

definitely boss's

add, goodness' sake and

conscience' sake.

I frequently use chrissake too.

[lilyfrog]

hmmm I would have ssid boss' cap.

The company I work for has a name that ends in "Arts" and in many of our official documents will mention things such us
".............Arts' policies" meaning the policies belonging to us,

Does tis rule apply because it is a name???

[Brugel]

The best way to decide is to say them out loud. You'll see (hear) that the boss' cap doesn't sound quite right.

[Narolines]

The singular possessive form is ALWAYS 's, regardless of the final letter of the noun in question.  Hence boss's, Jesus's, Keats's etc.   Just because you see "Keats' poetry" it doesn't mean it's right; you see lots of grammatical and spelling inaccuracies in lots of places that should know better (my local hospital, in a large metropolitan borough, had dozens of signs pointing to the "Emergencey Department" for years!).  "Goodness' sake" does, I agree, seem to reflect the way in which the words are usually spoken, but nonetheless it's grammatically wrong; and "conscience' sake" makes no sense at all - there is no use of an apostrophe without an s which could possibly indicate possession.  Again, I concede that that's the way it usually sounds when people say it, but it's horribly ugly in print and would have got a ring round it from my red pen when I was teaching English for a living.........

[Quizmonster]

I'm afraid you're not really correct, Narolines, in claiming that a singular possessive is ALWAYS 's. It's not just me saying so, by the way, but also Fowler's 'Modern English Usage', generally regarded as the 'bible' of current usage.
The horse's mouth specifically states that possessives of names such as Moses, Jesus, Bridges and others which end with the sound 'iz' rather than just 'z' or 's' (eg Burns or Thomas) do not require an s after the apostrophe. Accordingly, "Jesus' miracles" or "Jeff Bridges' performance in this film..." are perfectly correct and far from grammatical inaccuracies. Sorry, but that's the way it is.