Spanish Grammar/Relative pronouns

Relative pronouns are used to join a pronoun to an entire clause.

An example in English:

It was Lucy who sent the letter.

"Who sent the letter" is a relative clause and "who" is a relative pronoun. "Who" refers to the same thing as "it".

Masculine Singular Feminine Singular Masculine Plural Feminine Plural English
cuyo cuya cuyos cuyas whose
el cual la cual los cuales las cuales the one(s) who, the one(s) that
lo que that which, what, whatever
los que las que those who, those that
que que que que that, who, which