Relative pronouns
WHO
– is used for people
• Mr Smith, who is 85, still works in the bank.
WHICH
– is used for things
• The book which I got for my birthday is great.
THAT
– is used both for people and things
– it can be used only if it specifies the person or thing
• I'll show you the man that I am working with.
- it cannot be used to add some extra (unimportant information)
• My grandmother, who lives in the countryside, is a very lively woman.
BE CAREFUL!
– you can very often LEAVE OUT who, which and that.
– you can do it if the following sentence starts with a new subject
• I'd like to show you the girl I've fallen in love with.
- you cannot do it if the following sentence doesn't start with a new subject
• I'll lend you a book which really reads well.
WHOSE
- is used to express that the person or thing belongs to somebody or something
• The children whose parents don't have enough free time for them usually have social problems later in their life.
WHERE
– is used to join the sentence to some place
• The restaurant where we were having the celebration wasn't very good.