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Defining Relative Clauses

A defining relative clause gives essential information about the noun or noun phrase it modifies, without which the sentence wouldn’t make sense as the listener or reader would not be able to identify the noun in the sentence:

The hotel that we stayed in wasn’t bad. (‘that we stayed in’ tells the listener which hotel we are talking about; it defines the hotel)

‘Who’, ‘whose’ and ‘that’ can be used for people. ‘Which’ ‘whose’ and ‘that’ can be used for things.

See Also: Relative PronounNon-defining Relative ClauseRelative Clause Related ArticleRelative Clauses – Learn about Relative Pronouns in Non-Restrictive Clauses (Non-Defining clauses) and Restrictive Clauses (Defining clauses).

Non-defining Relative Clauses

non-defining relative clause gives extra information about a noun or noun phrase and has commas at both ends:

My sister, who lives in France, is coming to stay with me next week. (‘who lives in France’ is not essential, which means that I only have one sister and she does not need to be defined by the relative clause)

‘Who’ and ‘whose’ are used for people. ‘Which’ and ‘whose’ are used for things. ‘That’ cannot be used in a non-defining relative clause.

See Also: Defining Relative ClauseRelative Pronoun Related ArticleRelative Clauses – Learn about Relative Pronouns in Non-Restrictive Clauses (Non-Defining clauses) and Restrictive Clauses (Defining clauses).

Read more at http://www.usingenglish.com/glossary/non-defining-relative-clause.html#3JOSupB1Sc4QP0gW.99