Gerundio e forme perifrastiche

In Italian, the gerund (gerundio) is equivalent to the -ing verb form in English. To form the simple gerund, add the endings – ando (for the 1st conjugation: parlare>parlando) and -endo (for the 2nd and 3rd conjugation: leggere>leggendo, dormire>dormendo) to the stem of the verb. Please note the following forms:

fare>facendo
bere>bevendo
dire>dicendo

The gerundio may be used alone or in a subordinate clause to express the conditions (manner, cause, means) that relate to the main action. In this case, it corresponds to the English -ing form preceded by the words ‘while’, ‘by’, ‘on’, ‘in’, or ‘upon’.

Studiando, si impara - One learns by studying

Please note that the gerund must have the same subject as the verb in the main clause:

Ti ho visto camminando in centro - I saw you while (I was) walking in the city centre
Ti ho visto mentre camminavi in centro - I saw you while you were walking in the city centre

As in English, the gerund can be used to describe continuous actions. Periphrastic structures for the present continuous, the past continuous, and the future continuous are formed with the verb stare (not essere!) + verb + gerund, as follows:

Sto parlando con te - I’m talking to you
Ieri a mezzanotte stavo leggendo un libro - Yesterday at midnight I was reading a book
Domani a mezzanotte starò dormendo - Tomorrow at midnight I will be sleeping

Another periphrastic structure that is very used in Italian is stare per + infinitive ‘to be about to’:

Sto per uscire - I’m about to leave
Stavo per uscire quando Matteo è arrivato - I was about to leave when Matteo arrived