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P o r t u g u e s e O n l i n e

>>Verbs > Personal Infinitive

The personal infinitive is a complicated construction, especially when used in context. You will use it when the form of the Portuguese verb that has no person or number, known as the infinitive, must take a subject (person and number).

To form the personal infinitive, also called the inflected infinitive (inflections are grammatical endings on words), you will take the infinitive and add the following endings. See the section on subject pronouns for more information on the pronouns listed in the left column.

Unlike in English, it is not necessary to use a subject pronoun or a noun with the verb. Falarem and eles falarem both mean (for) them to speak. You may choose to use them when clarifying (ela falar for her to speak, when her is not already obvious from context) or emphasizing (eu falar for ME to speak).

The personal infinitive has several uses. It is common after prepositions, words like to, for, of. The phrases faça o favor de (vocês) falarem please speak (literally do the favor of (you) to speak) and para (nós) abrirmos a porta for us to open the door both contain prepositions before the infinitive.

This infinitive also allows you to make polite commands or requests, and is an alternative to the more direct imperative mood. (Você) não fumar no smoking (singular, said to one person) or (vocês) não fumarem no smoking (plural, to more than one person) are both more polite than não fume! don't smoke!.

The personal infinitive stands in for the subjunctive mood (pay special attention to the first in each series of examples): antes de (vocês) falarem before (all of you) speaking versus the present subjunctive in antes que (vocês) falem before all of you speak; pede para vendermos he asks for us to sell versus pede que vendamos he asks that we sell; apesar de falarmos despite our speaking versus embora falemos even though we speak. Notice that, in all four examples, the infinitive follows a preposition: de of, para for/in order to.

The personal infinitive is frequently found in phrases where the subject is a "dummy" or undefined "it": é impossível eles partirem (it) is impossible for them to leave, é incrível eles falarem inglês (it) is unbelievable for them to speak English. These constructions are also examples of the personal infinitive standing in for the subjunctive, since it is also possible to say é impossível que eles partam (it) is impossible that they leave or é incrível que eles falem inglês (it) is unbelievable that they speak English.

In constructions with ao "to the" + infinitive that would translate to "upon" + infinitive in English: ao vermos... upon seeing (it)..., ao venderem o livro upon selling the book, ao chegares (Portugal) upon your arrival, upon (you) arriving.

The personal infinitive is not used when it refers to someone who is already the subject of the sentence, unless it follows a preposition: (eles) esperam vender they hope to sell and not "eles esperam venderem", but são obrigados a venderem (they) are obliged to sell.