A relative clause is a dependent clause that cannot stand alone.  It is introduced by a pronoun that refers to a noun or pronoun (antecedent) in the preceding independent clause.
 

MAIN CLAUSE    // RELATIVE CLAUSE
 
 

The Atlantic is the ocean that separates Europe and Africa from America.
 

Der Atlantik ist das Meer, das Europa und Afrika von Amerika trennt.
 

In English, these relative pronouns include:  who, whom, which and that.

In German, the relative pronouns take the same forms as the definite articles, except in the DATIVE PLURAL.

You must have a comma between the main and the relative clauses, and the verb in the relative clause belongs at the end of the clause (dependent word order).
 
 

Case	Maskulin	Neutrum	Feminin	Plural
Nom	der	das	die	die
Akk	den	das	die	die
Dat	dem	dem	der	denen

 

While you will not be expected to produce relative pronouns this semester, you must be able
 

• identify a relative pronoun

• identify the antecedent (the word to which the pronoun refers)

• identify the case, number and gender of the pronoun (this is easy once you have found its antecedent)