1. DEFINING RELATIVE CLAUSES
These phrases define or identify which person or thing we are talking about:.
When the subject is a person we use who or that:
When the subject is a thing we use which or that:
When who, that or which is the object you can leave it out:
Whom is possible instead of who when it is the object of the verb:
Whose shows that something belongs to somebody:
The position of prepositions in relative clauses:
2. NON- DEFINING RELATIVE CLAUSES
These phrases add extra information. In these relative clauses that is not possible, we must always use who for people and which for animals or things.