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"La" is a definite article which is often translated as "the", and "las que" is a phrase which is often translated as "the ones that". Learn more about the difference between "la" and "las que" below.
la()
A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).
a. the
La pelota está en el tejado.The ball is on the roof.
La leche está en el refrigerador.The milk is in the refrigerator.
A pronoun is a word that stands in for a noun (e.g., she).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
las que
A phrase is a group of words commonly used together (e.g., once upon a time).
a. the ones that
Las entradas son numeradas, excepto las que dicen "sin numerar".The tickets have seat numbers, except for the ones that say "unnumbered."
b. the ones who (people)
María y Ana son las que organizaron la fiesta.María and Ana are the ones who organized the party.
