You will run into different opinions about that. Some would prnounce the 's as another syllable -ez; others will not and proniounce it the same as Charles.Originally Posted by vladz
I wrote an aswer to a similar question a few days ago, and I'll repeat it here:
This area is very confusing because different sources use different "rules". There is no universal standard. I'll give you some of the more common rules. You should pick the rule that works for you and then use it consistently. However, you will still run into others who have chosen differently.
Forming a possessive from a name ending in "s".
1. Always add 's to the end.
2. Always add 's to the end of one-syllable names. Add just an apostrophe to the end of names of two or more syllables.
3. Always add 's to the end unless that creates a repetition of the same sound at the end.
Moses' instead of Moses's
Jesus' instead of Jesus's
Narcissus' instead of Narcissus's
4. Add 's to the end if you would pronounce the new syllable. Add only an apostrophe if you wouldn't pronounce the new syllable.
Moses' = Moses
Moses's = Moseses