這本問(wèn)題本來(lái)我也在糾結(jié),不過(guò)現(xiàn)在我搞清楚了,我來(lái)回答你.剛看了書(shū),把書(shū)上的內(nèi)容搬過(guò)來(lái)給你,
Double genitive
The double genitive,also referred to as the "post genitive",is so called because it is a combination of the genitive and the of-phrase:
a friend of my brother's
some neighbours of my grandparents'
Note that the second noun in the double genitive construction almost always refers to persons,never to objects.
Also note that the first noun usually has indefinite reference (typically premodified by the indefinite article) and the second noun is always definite:
a friend of my brother's
some friends of my parents'
any friend of the doctor's
a lot of friends of that doctor's
Exceptions to the rule are the cases where the first noun is premodified by a demonstrative or postmodified by a relative clause:
that friend of my brother's
those ideas of your sister's
the friend of Bob's who was here last night