Using Apostrophes in English
The apostrophe may serve contracted verb forms and show belonging to titles/names.
The apostrophe often joins subjects with its verbs (in neutral/informal style) by replacing the first 1 or 2 letters in am/is/has/have/them. It also contracts not in negative verbs.
I’ve done it!
You can’t turn left here.
Another increasingly popular contraction is replacing g in informal –ing endings.
Will ya stop talkin’, hah?
‘s is put right after owners possessing following nouns (noun groups).
Jen’s new job is exciting.
John’s shirt is blue.
The men’s suits are black.
The horse’s hay is damp.
The horses’ hay is damp.
However with proper names with -s, we still add ‘s pronounced here as [iz].
It’s Charles’s birthday.
With 1 possession belonging to several owners, the apostrophe goes only after the last owner within its noun group.
John and Jen’s house
With possessions belonging to their respective owners, the apostrophe goes after each.
John’s and Jen’s houses are on the same street.