vs
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"Sus" is a form of "su", an adjective which is often translated as "his". "Los" is a definite article which is often translated as "the". Learn more about the difference between "los" and "sus" below.
los(
lohs
)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).
su(
soo
)An adjective is a word that describes a noun (e.g., the big dog).
a. his (masculine) (singular)
A word or phrase that is masculine (e.g., el libro).
A word or phrase that is singular (e.g., el gato).
¿Hiciste su tarea por él?Did you do his homework for him?
b. her (feminine) (singular)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is singular (e.g., el gato).
¿Sabes dónde está el cargador de su teléfono?Do you know where the charger is for her phone?
c. its (singular)
A word or phrase that is singular (e.g., el gato).
Esta es su perrera.This is its doghouse.
2. (formal) (possessive; second person singular)
A word or phrase used to refer to the second person formal “usted” by their conjugation or implied context (e.g., usted).