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"Se" is a form of "se", a pronoun which is often translated as "themselves". "Su" is an adjective which is often translated as "his". Learn more about the difference between "se" and "su" below.
se(
seh
)A pronoun is a word that stands in for a noun (e.g., she).
1. (reflexive)
2. (reciprocal)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Se dice que ganó su fortuna jugando al póquer.People say he won his fortune playing poker.
Se habla español.Spanish is spoken here.
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).