potere & riuscire
Grammatical centralie
The modal verb potere1 and the verb riuscire2 (as well as sapere) might translate to can in English, but they are not synonyms in Italian and have special usages.
Riuscire a + infinito means can or be able to in the sense of to manage. Some grammar texts often describe riuscire as being used when the ability to do/not do something is dependent upon ourselves or some physical limitation. In other words, whether we can or cannot do something is due to some factor or condition of ourselves (not on some outside force/factor):
Non riesco a uscire stasera; ho la febbre.
I can’t go out tonight; I have a fever.
Marta non riesce a giocare a tennis; si è rotta il braccio.
Marta can’t play tennis; she broke her arm.
In the example above, you are unable to do some task because of your own limitations due to being unwell. These expressions do not always have to be in the negative either:
Finalmente riesco a festeggiare; non sono più ammalato dopo tre settimane di Covid-19.
I can finally celebrate; I’m not sick anymore after three weeks of Covid-19.
In the example above, I can now do some task because I am no longer inhibited by my own limitations due to being ill.
We also use riuscire a + infinito when we can’t manage to do something, for example:
La porta è bloccata; non riesco a aprirla.3 Chiedi a Marco, è più forte!
The door is stuck; I can’t open it. Ask Marco, he’s stronger!
In this example, the use of riuscire a + infinito signals that the door won’t open because of my own physical limitations (I’m not strong enough).
Potere + infinito means can or to be able to in the sense of having the ability, freedom, opportunity, or capacity to do something. Some grammar texts describe the use of potere as when we rely upon some outside factor in allowing something to get done or not done.
Non posso uscire stasera; mia madre ha detto di no.
I can’t go out tonight; my mom said no.
In this example, my inability to go out has nothing to do with some aspect of myself that inhibits the activity; it is because my mother has forbad it. But what if my mom had a change of heart?
Sentite, ragazzi, posso accompagnarvi ora! Mia madre ha cambiato idea quando ho promesso di aiutarla domani.
Listen, guys, I can go with you now! My mom changed her mind when I promised to help her tomorrow.
And another example:
Non possiamo più seguire l’attualità online; Giovanni ha fatto scadere il nostro abbonamento.
We can’t follow current events online anymore; Giovanni let our subscription lapse.
In this example, our subscription lapsed because Giovanni forget to renew it, which is preventing us from reading the current events in the newspaper or online news site you frequent.
You can also express can with the verb sapere4 + infinito, which translates as to know how to do something or can:
Quei turisti sono persi e hanno bisogni di indicazioni. Credo che siano italiani!
Those tourists are lost, and they need directions. I believe they’re Italian!
Purtroppo non so parlare italiano.
Unfortunately, I can’t speak Italian.
Potere is irregular in the present tense: posso, puoi, può, possiamo, potete, possono.
Remember that riuscire, like uscire, is irregular in the present tense: riesco, riesci, riesce, riusciamo, riuscite, riescono.
In some cases, it is easy to know which verb to use. Potere could never be used in this context because the sentence makes it clear that the lack of the speaker’s strength is inhibiting the opening of the door, not some other factor. For potere to work in this example, the context would need to change: La porta è bloccata; non posso aprirla. Fiorella ha chiuso la porta a chiave. / The door is stuck; I can’t open it. Fiorella locked the door.
Sapere is also irregular in the present tense: so, sai, sa, sappiamo, sapete, sanno.
Potere is irregular in the present tense: posso, puoi, può, possiamo, potete, possono.
Remember that riuscire, like uscire, is irregular in the present tense: riesco, riesci, riesce, riusciamo, riuscite, riescono.
In some cases, it is easy to know which verb to use. Potere could never be used in this context because the sentence makes it clear that the lack of the speaker’s strength is inhibiting the opening of the door, not some other factor. For potere to work in this example, the context would need to change: La porta è bloccata; non posso aprirla. Fiorella ha chiuso la porta a chiave. / The door is stuck; I can’t open it. Fiorella locked the door.
Sapere is also irregular in the present tense: so, sai, sa, sappiamo, sapete, sanno.