Write sentences with all of/most of etc. + whom/which.
Julia has two sisters. (Both of her sisters are teachers.) Julia has two sisters, ***.
both of whom are teachers
Mary has three brothers. (All of her brothers are married.) Mary has three brothers, all of whom are married.
We were given a lot of information. (Most of the information was useless.) We were given a lot of information, most of which was useless.
There were a lot of people at the party. (I had met only a few of these people before.) There were a lot of people at the party, only a few of whom i had met before.
I have sent her two letters. (She has received neither of these letters.) I have sent her two letters, neither of which she has received.
Ten people applied for the job. (None of these people were suitable.) Ten people applied for the job none of whom were suitable.
Kate has got two cars. (She hardly ever uses one of them.) Kate has got two cars, one of which she hardly ever uses.
Norman won 50,000 pounds. (He gave half of this to his parents.) Norman won L50,000, half of which he gave to his parents.
Julia has two sisters. (Both of her sisters are teachers.) Julia has two sisters, both of whom are teachers.