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"Las que" is a phrase which is often translated as "the ones that", and "los" is a definite article which is often translated as "the". Learn more about the difference between "las que" and "los" below.
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.
los()
A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).
A pronoun is a word that stands in for a noun (e.g., she).
