WHO/WHICH/-/WHOSE
Who and which are relative pronouns, they connect two sentences .
That’s the girl …… broke my glasses.
That’s the girl WHO broke my glasses.
The boy …… called her was gone.
The boy WHO called her was gone.
When the relative pronoun refers to (says something about) a person you have to use WHO.
That’s the bus …… had an accident.
That’s the bus WHICH had an accident.
That’s the bike …… was stolen yesterday.
That’s the bike WHICH was stolen yesterday.
When the relative pronoun refers to (says something about) a thing you have to use WHICH.
You can leave WHO or WHICH out if there is a new subject directly after it:
When the relative pronouns refers to something that someone owns you use WHOSE.
That’s the girl …… I gave money to.
That’s the girl WHO I gave money to.
That’s the girl I gave money to.
That’s the bus …… I missed yesterday.
That’s the bus WHICH I missed yesterday.
That’s the bus I missed yesterday.
There are the girls ….. house burned down.
There are the girls WHOSE house burned down.
There is the woman ….. bike was stolen.
There is the woman WHOSE bike was stolen.