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"Sonreír" is an intransitive verb which is often translated as "to smile", and "sonreírse" is a pronominal verb which is also often translated as "to smile". Learn more about the difference between "sonreír" and "sonreírse" below.
sonreír()
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
2. (to favor)
a. to smile on
Parece que la vida me sonríe: al fin he encontrado un trabajo donde me valoran de verdad.It seems that life smiles on me: I have finally found a job where I'm really valued.
sonreírse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
sonreírse()
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
sonreír
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
3. (to favor)
a. to smile on
Parece que la vida me sonríe: al fin he encontrado un trabajo donde me valoran de verdad.It seems that life smiles on me: I have finally found a job where I'm really valued.