When the condition is not true
The periodo ipotetico della possibilità describes a condition that is not met right now, or that stays highly unlikely, and what would follow if it were. I have no time. If I had some, I would come.
English builds this from a plain past after if and would in the main clause. Italian keeps the would half as the condizionale presente, but refuses the plain past after se. It demands the congiuntivo imperfetto. You already know a fragment of this: in if I were you, English uses were instead of was. Italian does that with every verb.
Three sentences to tune your ear
Se avessi tempo, verrei volentieri.
If I had time, I'd gladly come.
Se fossi ricco, viaggerei tutto l'anno.
If I were rich, I'd travel all year round.
Se potessi, cambierei lavoro domani.
If I could, I'd change jobs tomorrow.
The forms for the se clause
The congiuntivo imperfetto is built from the infinitive stem plus -assi, -essi or -issi, depending on the verb class.
The verbs this pattern actually needs
| Infinitive | Congiuntivo imperfetto |
|---|---|
| parlare | parlassi |
| prendere | prendessi |
| dormire | dormissi |
| avere | avessi |
| potere | potessi |
| sapere | sapessi |
| essere | fossi |
| fare | facessi |
Form for io and tu.
Only essere (fossi, not essessi) and fare (facessi) have an irregular stem. The others follow the infinitive, including avere, potere and sapere. English modals disappear into single words here: if I could is se potessi, if I knew is se sapessi.
What the second type is for
Unreal or unlikely conditions
The condition is not the case right now, or hardly imaginable. The se clause can also come last.
Se abitassi più vicino, ci vedremmo più spesso.
If you lived closer, we'd see each other more often.
Se vincessi alla lotteria, comprerei una casa al mare.
If I won the lottery, I'd buy a house by the sea.
Verrei volentieri, se avessi tempo.
I'd gladly come if I had time.
Polite advice
Se fossi in te is the Italian if I were you. Note the in: Italian says, literally, if I were in you.
Se fossi in te, non ci andrei.
If I were you, I wouldn't go.
Se fossi in te, prenderei un taxi.
If I were you, I'd take a taxi.
Possible or not?
Se ho tempo, vengo.
If I have time, I'll come. (quite possible)
Se avessi tempo, verrei.
If I had time, I'd come. (but I don't)
