EL/LA/LOS/LAS QUE, EL/LA CUAL, LOS/LAS CUALES
The relative pronouns el/la/os/las que, el/la cual, los/las cuales are used in exchange for quien, quienes, hence when the sentence refers to people.En mi casa la que (quien) limpia es mi madre y el que (quien) cocina es mi padre.
In my house my mother is the one who cleans and my father is the one who cooks.
En esa foto están mis amigos a los que (a quienes) voy a visitar a fin de mes.
In that picture there are the friends to whom I'm going to visit at the end of the month.
We also use these pronouns when the sentence is introduced by a preposition but we can't use quien, quienes because the sentence refers to things and not people. When talking about things, the use of el/la/los/las que or el/la cual or los/las cuales is interchangeable.
Aquí estaba la casa en la que (en la cual) me crié, pero fue derribada hace algunos años.
The house in which I grew up in was here, but it was demolished a few years ago.
We use el/la cual or los/las cuales or el/la/los/las que to select between different options.
Estos libros, los que sacamos de la biblioteca, son muy interesantes.
These books, the ones we took from the library, are very interesting.
*the books we took from the library are interesting, but the ones we already had were not.
El director, el cual dirigió varias películas este año, ganó el premio.
The movie director, the one who directed a few movies this year, won the award.
*there's a few movie directors but we refer to the one who directed a few movies this year.
We use el/la cual or los/las cuales instead of el/la/los/las que to:
1.- clarify
Estas películas, las cuales me trajiste el otro día, me han ayudado para mi clase de psicología.
These movies, which you brought to me the other day, have helped me for my psychology class.
*the person clarifies that those movies the other friend lent him have helped him for his class, not other movies.
2.- avoid ambiguity
La novia de mi amigo, la cual vive en Londres, trabaja para la ONU.
My friend's girlfriend, who lives in London, works for the UN.
*if we used "que", it would not be clear who lives in London, the friend or the girlfriend.
The el/la/os/las que pronouns can also be used as the subject of a sentence.
El que quiera un helado que levante la mano.
Whoever wants ice cream, raise his hand.
CUYO, CUYA, CUYOS, CUYAS
The relative pronouns cuyo, cuya, cuyos, cuyas express possession and they have to agree with the person or thing possessed in grammatical gender and number. These pronouns usually agree with the noun that comes after them.Dalí, cuyas obras son conocidas mundialmente, murió en 1989 en Figueres.
Dali, whose works are widely known, died in 1989 in Figueres.
Ayer conocí al chico cuyo padre es el presidente del equipo de fútbol de la ciudad.
Yesterday I met the guy whose father is the president of the city's soccer team.
These relative pronouns are commonly used in the written language but not so often in the spoken language besides in formal situations or speeches.