Se me olvidó el cuaderno.

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Breakdown of Se me olvidó el cuaderno.

• me: me
• el cuaderno: the notebook
• olvidarse: to forget

Questions & Answers about Se me olvidó el cuaderno.

What does the se do in Se me olvidó el cuaderno?

It’s the pronominal marker used in the so‑called accidental se construction. It turns focus away from the person and onto the event, implying the forgetting was unintentional. It doesn’t mean “to him/her/it” here and doesn’t stand for a separate person.

Why is the verb olvidó in third person if I’m the one who forgot?

Because the grammatical subject is the thing forgotten: el cuaderno. The verb agrees with that subject (3rd person singular). If the subject were plural, you’d say: Se me olvidaron los cuadernos.

Who/what is the subject in this sentence?

El cuaderno is the subject. The person affected (you) is expressed by the indirect object clitic me.

What does me express here?

Me is an indirect object meaning “to/for me,” indicating who is affected by the event. Literally: “The notebook forgot itself on me.”

How is Se me olvidó el cuaderno different from Olvidé mi cuaderno?