You probably think of “se” as the Portuguese equivalent of “if,” and rightly so:

Se eu pudesse… = If I could…

Also, reflexive verbs may come to your mind:

Ela magoou-se no joelho.
She hurt herself in the knee. 

Now, what you might be missing is “se” as an impersonalizing particle:

Vai-se muito à praia no Verão.
People go to the beach a lot in the summer.

See, that “vai” (ir) followed by “se” is not a reflexive verb. The fact that the verb is in the 3-person and followed by “se” makes the sentence impersonal, as in “people…”

Let’s dive in.

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Está-se bem junto ao mar

Fill in the blanks with the missing verbs to complete the impersonal sentences.

Fill in the blanks

Tudo se alcança

Fill in the blanks with the impersonal verb forms.

Fill in the blanks

1. Generalizations

Here’s an example of a generalizing statement: 

(a) As pessoas bebem em demasia nos dias que correm.
People drink far too much these days.

The previous sentence doesn’t refer to anyone specifically: “people”…

Alternatively, we can make this kind of generalization by using the verb in the 3-person (“bebe”) followed by “-se”:

(b) Bebe-se em demasia nos dias que correm.

If we change the tense, the same principle applies; the only difference is that now our verb comes in the 3-person of the Past tense (P. Imperfeito in this case):

(a) Antigamente as pessoas bebiam em demasia.
(b) Antigamente, bebia-se em demansia.
In the old days, people drank too much.

2. Passive Voice

The impersonalizing agent “se” is also used in passive-voice constructions, which are impersonal by definition.

For instance, the sentence “As pequenas e médias empresas geram a maior parte da riqueza da economia” (“Small and medium-sized enterprises create most of the economy’s wealth”) can be rewritten into a passive-voice construction (hidden agent):

(a) A maior parte da riqueza da economia é gerada por pequenas e médias empresas.
Most of the economy’s wealth is created by small and medium-sized businesses.

Alternatively, we can use verb form in the 3-person followed by “-se”, just as we did before:

(b) A maior parte da riqueza da economia gera-se através de pequenas e médias empresas.

If we change the tense, the principle remains; the only difference is that now our verb form comes in the 3-person of the Past tense (P. Imperfeito in this case):

(a) Antigamente, a maior parte da riqueza da economia era gerada por pequenas e médias empresas.
(b) Antigamente, a maior parte da riqueza da economia gerava-se através de pequenas e médias empresas.
Back in time, most of the economy’s wealth was created by small and medium-sized businesses.

3. Ad Copy

Finally, our generalizing formula – verb form in the 3-person followed by “-se” – is commonplace in ad copy, which tends to be concise and hide the subject agent: 

Vende-se terreno.
Land for sale.

Aluga-se quarto.
Room for rent.

Notice that if the object is plural, then we use the 3-person plural:

Vendem-se terrenos.
Alugam-se quartos.

One last note. The default word order is the verb followed by “se” (with a hyphen in between). There are nonetheless situations where they will change places as is the case for reflexive or object pronouns. You can learn more about word order between verb forms and object/reflective pronouns in either of the following articles:

• Portuguese Reflexive Verbs and Pronouns
• Portuguese Object Complements and Pronouns