12.3.3 particularities in the combinaison of pronouns and si
We have already spoken in chapter six about the problems occurring when the si of the si impersonale or the sipassivante is used together with other pronouns. But at that time we had not already explained the use of the si passivante / si impersonale and therefore it was perhaps to complicated. Let's discuss these combinations once again.
The si of the si impersonale combined with the reflexive pronoun si
There are verbs that are always reflexive and verbs which can be used in a reflexive way. Always reflexive are for instance the verbs ammalarsi (to fall ill), arrabbiarsi (to become angry), accorgersi (to notice something).
Il mio amico si è ammalato dopo avere mangiato troppo.
My friend felt ill after having eaten to much.
Quando si rese conto che l' avevano ingannato si arrabbiò.
When he remarked that he had been duped, he became angry.
Mi sono accorto di questo problema la prima volta che me l' hanno detto.
I got aware of this problem the first time when it was told to me.
The following verbs can be reflexive: Alzarsi, chiamarsi
Mi sono alzato per andare a scuola.
I got up to go to school.
Mi chiamo Lorenzo.
My name is Lorenzo.
But for the further discussion it is irrelevant if the verb is always reflexive or can be reflexive. The important thing is that the pronoun si in the si impersonale (in this case it is an indefinite pronoun) as well as in the si passivante (in this case it is a reflexive pronoun, at least from a grammatical point of view) can be combined with the reflexive pronoun si.
In this case one would get two si, one of the si impersonale / si passivante and the other really reflexive pronoun.
two following si in the si impersonale: Ci si lava => One washes oneself.
two following si in the si passivante: Ci si lavano le teste => One washes oneself the heads
~Si si lava.~ (The sentence is WRONG. The correct form is Ci si lava<=> One washs onself)
In the case that one si follows another si si becomes ci si.