1. ANTE TODO
The word “se” is often used in Spanish in a variety of ways. It can be very confusing.
When you learned indirect and direct object pronouns, you learned that you are not able to use the indirect object pronouns le or les before lo, la, los, or las. Instead, you changed them to “se.” In that case, “se” was used as the indirect object pronoun. (i.e. le lo = se lo)
Indirect: me, te, le, nos, os, les
Direct: me, te, lo/la, nos, os, los, las

2. You also learned how to use se as the third person reflexive pronoun (Él se despierta. Ellos se visten. Ella se baña.). In that case “se” agrees with the subject, and usually means: himself, herself, yourself, yourselves, themselves.
Yo me lavo. I wash myself Nosotros nos lavamos. We wash ourselves.
Tú te lavas. You wash yourself Vosotros os lávais You wash yourselves.
Ud./Él/Ella se lava Uds./Ellos/Ellas Se lavan.
You wash yourself. You wash yourselves.
He washes himself. They wash themselves.
She washes herself. They wash themselves.

3. Se can also be used to form constructions in which the person performing the action is not expressed or is de-emphasized.
Impersonal (passive)
Unplanned events (unintentional)

4. Impersonal constructions with se
In Spanish, verbs that are not reflexive can be used with se to form impersonal constructions. These are statements in which the person performing the action is not expressed or defined. In English, the passive voice or indefinite subjects (you, they, one) are used.
ACTIVE VOICE:
Los españoles hablan español en España.
subject verb d.object
The Spaniards speak Spanish in Spain.
PASSIVE VOICE
Se habla español en España.
Verb passive Subject
Spanish is spoken in Spain.

5. Se puede leer en la sala de espera.
You can read in the waiting room. (One can read in the waiting room.)
Se hacen operaciones aquí.
They perform operations here. (Operations are performed here.)
Se necesitan medicinas enseguida.
They need medicine right away. (Medicine is needed right away.)

6. ¡ATENCIÓN!
Note that the third person singular verb form is used with singular nouns and the third person plural form is used with plural nouns:
Se vende aspirina.
Se venden antibióticos.

7. Impersonal constructions with se
You often see the impersonal se in signs, advertisements, and directions. Note: If the verb is not followed by a noun, use the singular form of the verb.
Se prohíbe nadar. Se come muy bien en este restaurante.
Swimming is prohibited. One eats very well in this restaurant.
No se puede entrar.
One can’t enter.
Se necesitan programadores.
Programmers are needed.
Se entra por la izquierda.
One enters through the left.

8. While signs and advertisements primarily use the present tense for the passive voice, you can use any tense in the passive voice.
For example. If you were describing life in the past, for instance in 1960, you might use the imperfect passively to express:
Se llevaban minifaldas. (Mini-skirts were worn.)
Se escuchaba música roc. (One listened to rock and roll music.)

9. Se for unplanned events
Se is also used to form statements that describe accidental or unplanned events. In this construction, the person who performs the action is de-emphasized, so as to imply that the accident or unplanned event is not his or her direct responsibility. You will find that these statements are commonly expressed using the preterit and are constructed using the following pattern.

10. Se for unplanned events
se OBJECT VERB SUBJECT
PRONOUN
Se me perdió el libro.
In this type of construction, what would normally be the direct object of the sentence becomes the subject, and it agrees with the verb, not with the indirect object pronoun.
i.e. Perdí el libro. I lost the book. (I take the blame.)
Se me perdió el libro. The book got lost.
The book lost itself from me.

11. Verbs commonly used with se
The following verbs are the ones most frequently used with se to describe unplanned events.
caer
to fall; to drop
perder (e:ie)
to lose
dañar
to damage; to break down
quedar
to be left behind
olvidar
to forget
romper
to break

12. Se for unplanned events
I.O. PRONOUN VERB SUBJECT
me, te, le quedó la receta.
cayó SINGULAR la taza.
Se dañó la radio.
nos, os, les rompieron las botellas.
olvidaron PLURAL las pastillas.
perdieron las llaves.

13. Se me perdió el teléfono de la farmacia. Se nos olvidaron los pasajes.
I lost the pharmacy’s phone number.
Se nos olvidaron los pasajes.
We forgot the tickets.

14. Al paciente se le perdió la receta.
To clarify or emphasize who the person involved in the action is, this construction commonly begins with the preposition a + [noun] or a + [prepositional pronoun].
Al paciente se le perdió la receta.
The patient lost his prescription.
A Diana se le olvidó ir al consultorio ayer.
Diana forgot to go to the doctor’s office yesterday.
A mí se me cayeron los cuadernos.
I dropped the notebooks.
A ustedes se les quedaron los libros en casa.
You left the books at home.

15. ¡ATENCIÓN!
While Spanish has a verb for to fall (caer), there is no direct translation for to drop. Dejar caer (let fall) is often used to mean to drop.
El médico dejó caer la aspirina.
The doctor dropped the aspirin.
Al médico se le cayó la aspirina.
The aspirin dropped itself from the doctor.

16. ¡INTÉNTALO! Completa las frases de la columna A con se impersonal y los verbos correspondientes en presente. A
(enseñar) ______ cinco lenguas en esta universidad.
Se enseñan
2. (comer) ______ muy bien en la cafetería.
Se come
3. (vender) ______ muchas pastillas allí.
Se venden

17. 4. (servir) ______ platos exquisitos cada noche.
Se sirven
5. (necesitar) ______ mucho dinero.
Se necesita
6. (buscar) ______ secretaria.
Se busca

18. ¡INTÉNTALO! Completa las frases de la columna B con se
y los verbos en pretérito para expresar sucesos imprevistos. B
(I broke) ______ las gafas.
Se me rompió
2. (You (fam.) dropped) ______ las pastillas.
Se te cayeron
3. (They lost) ______ la receta.
Se les perdió
2 of 2

19. 4. (You (form.) left) ______ aquí la radiografía.
Se le quedó
5. (We forgot) ______ pagar la medicina.
Se nos olvidó
6. (They left) ______ los antibióticos en la clínica.
Se les quedaron