We discuss once again the possibilities to shorten a subordinate clause with an infinitivo in Portuguese. Normally grammars focus on the use of the infinitivo pessoal, which is without any doubt a speciality of Portuguese. However the infinitivo pessoal is not the real problem. The infinitivo pessoal can be used in any circumstances where the infinitivo can be used. It is not enough to just say that the infinitivo pessoal is to be used if it has its own subject that differs from the main clause, that it must be used if the subject is explicitely mentioned, etc.. because that is obvious and not the real problem. The real problem is to understand when the infinitive can be used. The infinitivo pessoal can be used in almost any circumstances where the infinitivo can be used. (Obviously it can be used if the infinitive is the subject or the direct object of the sentence. In a sentence like "To write a book is not easy" the infinitive is the subject itself. In a sentence like "He refused to obey" the infinitive is the direct object. In these cases personal endings wouldn't make any sense.)
What really is to be understood is the use of the infinitive in shortening relative clauses. If this is understood it is eays to understand that in some special cases only the infinitivo pessoal can be used. The infinitivo pessoal is not the problem. The use of the infinitive is the problem.
A subordinate clause introduced by a conjunction can be shortened with an infinitive if there exists a preposition that corresponds semantically to the conjunction. The infinitive (pessoal) is a verbal noun and has the same syntactical function as a noun, can therefore be used together with a preposition. (However not together with a conjunction.)Very often the scheme is simple. The conjunction has que, despois que (after) and in the preposition the que is substitiuted by de, depois de (after) or the que simply left out, mesmo que (even if) <=> mesmo (even).
|subordinate clause||Eu chorei por horas, depois que eu vi isso.|
|I cried for hours after I have seen that. .|
|construction with an infinitive:||Eu chorei por horas, depois de ver isso.|
|subordinate clause:||O fez sem que tinha perguntado.|
|He did it, without having asked.|
|construction with an infinitive::||O fez sem perguntar.|
|He did it, without having asked.|
To the conjunction sem que exists a corresponding preposition, sem, and therefore a substitution with an infinitive is possible. Furthermore it is useful to see that in most cases the portuguese infinitive is translated with an English gerund. The English gerund has a completely different syntactical function than the Portuguese gerundio. The English gerund is verbal noun, can have the syntactical function of a noun. The Portuguese gerundio resembles more to an adverb has the syntactical function of an adverb. To the Portuguese gerundio corresponds the English present participle. Both, the present participle and the gerund are -ing forms and some people may therefore be induced to believe that there is no difference between a gerund and a present participle, but that is not true.
The shortening of a subordinate clause works more or less in all indogermanic languages, at least in the languages this author knows and the scheme is always the same. If there is a preposition that semantically corresponds to the conjunction a subordinate clause can be shortened with an infinitiv. This works as well in Persian. (In opposite to what most people believe, Persian has nothing to do with Arabic. Persian is an indogermanic language.)
|He runs without food..|
|U bedoone ghaza midavad.|
|او بدون غذا میدود.|
|He runs without eating..|
|U bedoone ghaza khordan midavad.|
|او بدون غذا خوردن میدود.|
|He runs, although he hasn't eaten anything.|
|U bedoone inkeh ghaza bekhorad midavad.|
|او بدون اینکه غذا بخورد میدود.|
The Portuguese infinitivo is in general translated with a gerund in English. The English gerunds inherits in general the subject from the finite verb. (Although there are some exceptions. The direct object of the finite verb can become the subject of the gerund: I saw him leaving the train.) In the following example the infinitivo inherits the subject from the finite verb. With an infinitivo pessoal one could change that.
|Oposição venezuelana diz que não dialogará com governo até receber garantias.|
|The opposition of Venezuela says, that as long as they don't get guarantees, they will not talk to the government.|