Verbos modais: poder, dever, ter que, precisar, saber + infinitivo
Verbos modais: poder, dever, ter que, precisar, saber + infinitivo means “The modal-type verbs (poder, dever, ter que, precisar, saber) join directly to an infinitive to express permission, possibility, obligation, need or skill”. Portuguese uses a handful of modal-type verbs, each conjugated while the following verb stays in the infinitive. Formation: poder / dever / ter que (ter de) / precisar / saber + infinitivo — precisar perde o de antes do infinitivo
The modal-type verbs (poder, dever, ter que, precisar, saber) join directly to an infinitive to express permission, possibility, obligation, need or skill
B1Formation
poder / dever / ter que (ter de) / precisar / saber + infinitivo — precisar perde o de antes do infinitivo
Explanation
Portuguese uses a handful of modal-type verbs, each conjugated while the following verb stays in the infinitive. Poder = can/may, covering both permission (Posso entrar? = May I come in?) and possibility (Pode chover = it may rain). Dever = should for advice (Você deve descansar = you should rest) but also probability, exactly like Spanish deber de: Ele deve estar em casa = he's probably home. Obligation is ter que / ter de + infinitive (Tenho que trabalhar); in everyday Brazilian speech ter que dominates and ter de sounds formal, while precisar (de) means need to and, crucially, drops the de before an infinitive: Preciso ir, never "preciso de ir". Finally, keep saber (know how to, by learned skill: Sei nadar = I can swim) apart from poder (be able to by circumstance: Não posso nadar hoje = I can't swim today).
Examples
Note
Spanish speakers get a nearly free ride: poder=poder, dever=deber, ter que=tener que, saber nadar=saber nadar. The one trap is precisar, which drops de before an infinitive (Preciso ir), unlike gostar which keeps it.
FAQ
Verbos modais: poder, dever, ter que, precisar, saber + infinitivo — what does it mean and how is it used?
The modal-type verbs (poder, dever, ter que, precisar, saber) join directly to an infinitive to express permission, possibility, obligation, need or skill. Portuguese uses a handful of modal-type verbs, each conjugated while the following verb stays in the infinitive. Poder = can/may, covering both permission (Posso entrar? = May I come in?) and possibility (Pode chover = it may rain). Dever = should for advice (Você deve descansar = you should rest) but also probability, exactly like Spanish deber de: Ele deve estar em casa = he's probably home. Obligation is ter que / ter de + infinitive (Tenho que trabalhar); in everyday Brazilian speech ter que dominates and ter de sounds formal, while precisar (de) means need to and, crucially, drops the de before an infinitive: Preciso ir, never "preciso de ir". Finally, keep saber (know how to, by learned skill: Sei nadar = I can swim) apart from poder (be able to by circumstance: Não posso nadar hoje = I can't swim today).
Verbos modais: poder, dever, ter que, precisar, saber + infinitivo — how do you form it?
poder / dever / ter que (ter de) / precisar / saber + infinitivo — precisar perde o de antes do infinitivo
Verbos modais: poder, dever, ter que, precisar, saber + infinitivo — any usage notes?
Spanish speakers get a nearly free ride: poder=poder, dever=deber, ter que=tener que, saber nadar=saber nadar. The one trap is precisar, which drops de before an infinitive (Preciso ir), unlike gostar which keeps it.