The Group Genitive
When a single noun is used in the genitive this genitive is termed
individual: Europe’s future, the horse’s tail. But the inflexion
–‘s can refer to a phrase. This genitive is termed the group
genitive. For example: John and Jack’s father ,the quarter of an
hour’s sleep.
The Double Genitive.
The double genitive is a combination of the preposition
“of” and
a noun in the genitive case:a friend of John’s , a doll of the
child’s.
Here the relation of possession is expressed twice by the preposition
“of” and the –‘s genitive , hence the term “double genitive”.
The noun in the genitive case must be both definite and
personal. The
noun preceding the of-phrase can’t be proper
Sometimes the double genitive can be used for the stylistic
purpose:That long nose of John’s!