Conjugating the Portuguese

The logic behind this rule is surprisingly simple. Usually, we use the Personal Infinitive when the subject of the infinitive is different from the main verb. Imagine you are at a restaurant. You say, "I brought the wine for us to drink." In English, "drink" does not change. In Portuguese, you use the nós form of the infinitive. This tells everyone exactly who is doing the drinking. It removes all doubt. If the main verb and the infinitive have the same subject, you often stay with the basic form. But when they split, the Personal Infinitive steps in. It acts as a bridge between ideas. It allows you to keep the sentence structure simple while being grammatically precise. It is essentially a shortcut. Instead of using a long que clause with the subjunctive, you can often use a preposition and this personalized infinitive. It keeps your speech fluid and punchy. Even native speakers sometimes debate the nuances. However, the core idea is always about identifying the "owner" of the action.

1. 1Creating these forms is a breeze. You start with the base infinitive of any verb. Then, you simply glue on the specific endings. It is much easier than the present or past tenses.
2. 2For eu (I), use the base infinitive. No change needed here.
3. 3For tu (you, informal), add -es. So falar becomes falares.
4. 4For você/ele/ela (you/he/she), use the base infinitive again. It stays simple.
5. 5For nós (we), add -mos. Now comer becomes comermos.
6. 6For vós (you all, archaic), add -des. This is rare, but good to know.
7. 7For vocês/eles/elas (you all/they), add -em. Thus partir becomes partirem.
8. 8Note that irregular verbs follow this same pattern. Even ser or ir use their infinitives as the base. You just take ser and add -em to get serem. No weird stem changes to worry about! It is like building with Lego blocks. The base is always the same, and the endings just click into place.

You will mainly use this after certain prepositions. The most common one is para (for/in order to). If you say "Para eles entenderem, precisamos de falar devagar," you are using it perfectly. Another trigger is ao (upon). Use it to describe something happening right at that moment. "Ao saírem do escritório, começou a chover" means "Upon them leaving the office, it started raining." It is also common after sem (without), antes de (before), and depois de (after). You might also use it for emphasis. Sometimes the subject is the same, but you want to be extra clear. For example, in a job interview, you might say: "Estou aqui para provarmos que sou o melhor." This highlights the "we" aspect of the proof. It is also great when the subject is not clearly defined by the rest of the sentence. If you see a sign that says "É proibido fumarem aqui," it specifically tells a group of people to stop. It feels more direct and personal than a general ban. Think of it like a grammar traffic light—it tells everyone exactly when it is their turn to act.

Do not use it if the subject is truly impersonal or general. If you are making a broad statement like "Viver é bom" (Living is good), keep it simple. There is no specific person "living" here. It is just the concept of life. Also, if the subject is already perfectly clear and there is no risk of confusion, the regular infinitive is often fine. You do not need to over-conjugate. If you say "Quero comer," everyone knows *you* want to eat. Adding an ending there would just sound strange. It would be like wearing a tuxedo to a beach party. You are being too formal and technical for no reason. Another trap is when the infinitive acts as a noun. In "O cantar dos pássaros," the word "cantar" is a noun. You would not conjugate it there. Keep an eye out for these general cases. If the sentence is about everyone or no one in particular, stick to the basic form.

The biggest mistake is confusing this with the Future Subjunctive. For regular verbs, they look exactly the same! This is a cruel joke from history. However, for irregular verbs, they are different. Ter becomes tiver in the subjunctive, but stays ter in the Personal Infinitive. Watch out for that. Another mistake is forgetting the -em for the third person plural. People often say para eles fazer instead of para eles fazerem. It sounds incomplete, like a sentence without a period. Also, be careful with the tu form. Adding -es is essential if you are being informal. If you forget it, you might sound like you are speaking a simplified version of the language. Lastly, avoid using it when the subject is the same as the main verb. "Eu vim para eu comer" is redundant and clunky. Just say "Eu vim para comer." Your goal is to be efficient, not repetitive. Yes, even native speakers mess this up sometimes, so do not panic if you trip over your tongue.

Compare the Personal Infinitive with a que clause using the subjunctive. "Para que nós vamos" vs "Para irmos." The second one is much shorter. It feels more modern and conversational. The subjunctive version is often more formal or used for specific emphasis. Also, compare it with the Impersonal Infinitive. The impersonal form is like a ghost; it has no body. The personal form has a clear face. In English, we often use the "-ing" form or "for... to..." to translate these. "Before leaving" vs "Before they leave." Portuguese just gives you a more precise way to handle these differences without needing extra words. It is like having a multi-tool in your pocket instead of a whole toolbox. It does the job of several different structures at once.