Relative clauses.
Relative clauses are subordinate sentences. They have an antecedent in the main sentence. They modify or specify this antecedent.
Defining relative sentences.
- They modify the antecedent so that it makes it different from the rest of its class.
- They contain essential information to understand the main sentence.
- They are not separated with commas.
Non-defining relative sentences
- The antecedent is already determined, it doesn't need to be specified.
- They don't contain essential information to understand the sentence.
- They are always separated by commas.
- The relative pronoun can never be omitted.
Relative pronouns
We can also use WHEN for times and WHERE for places.
Omission of the relative pronoun
The relative can be omitted:
- in defining relative clauses.
- when the pronoun is the object of the relative clause.
- never when it is the subject.
Ex: The girl he likes is my best friend.
Ex: The boy who is next to the door is my brother.
Defining and non-defining.
Ex: My sister, who lives now in London, is my best friend.
(Adapted from A Practical English Grammar. OUP)
Subject Object Possessive
For people Who Whom/who Whose
For things Which Which Whose/of which
Non-defining relative pronouns
Subject Object Possessive
For people Who Whom/who Whose
That That
For things Which Which Whose/of which
that that
Defining relative pronouns
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