A relative pronoun connects a dependent
clause to a main clause and refers to something
already mentioned (the antecedent.) This pronoun
may serve as the subject or object of a verb, or
the object of a preposition. Que and
quien are the most commonly used relative
Que (who, whom, that, which)
refers to persons or things, except after a preposition,
when it refers to things only. El que (and
its forms - la que, los que, las que) and el cual
(and its forms - la cual, los cuales, las cuales)
may replace que or quien. These pronouns are
used for clearness when there are two antecedents,
and with prepositions.
La casa en que vivo es pequeña.
The house in which I live is small.
He visitado la ciudad cerca de la cual vive.
I visited the city near which he lives.
Quien (-es) (who) is used
in a supplementary clause. When used with
a preposition, it means whom. Quien
(-es) is often used in place of el que
and its forms as well, when it means one who,
those who, etc.
Lo que and lo cual (which)
refer to the whole sentence.
Cuyo (-a, -os, -as) is a possessive
adjective and it agrees in gender and number with
the thing possessed, which is always the word that