Relative clauses

Relative clauses are used to give additional information about something (person, place or thing) without starting another sentence. They are introduced by relative pronouns or adverbs. There are two types of relative clauses: Defining and Non-defining.

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 book that I lent you is my favourite. (It is this particular book, not another one).

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

Mary Jones, who is my best friend, is coming to the party tonight. (the relative clause is not essential here).

Explanation in English.
Explanation in Spanish.

Exercises on Relative Clauses (English Gramar Online)

Relative Pronouns and Relative Adverbs
Exercise on Relative Pronouns Level: elementary
Subject Pronouns or Object Pronouns? Level: lower intermediate
Relative Pronouns – Necessary or not? Level: lower intermediate
Relative Pronouns – Necessary or not? Level: upper intermediate
Relative Adverbs Level: intermediate
Relative Pronouns in the Text „Stonehenge“ (who/which) Level: elementary

Relative Clauses and Contact Clauses (without the relative pronoun)
Relative Clauses - Formation Level: elementary
Contact Clauses Level: lower intermediate
Definitions with Relative Clauses Level: intermediate
Relative Clauses - defining or non-defining? Level: upper intermediate
Non-Defining Relative Clauses Level: upper intermediate
Forming Relative Clauses - defining and non-defining Level: upper intermediate
Relative Clauses in the Text „San Francisco“ Level: elementary

Tests
Relative Clauses: Level 1 • Level 2 • Level 3 • Level 4

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