Passive Voice: Introducing Agents

In a normal active sentence, the subject does the action. "The chef cooked the meal." In the passive voice with an agent, the meal becomes the subject. The chef moves to the end of the sentence. You introduce this chef using the preposition por. This preposition usually merges with articles. So, por + o becomes pelo. por + a becomes pela. It is like a grammar traffic light. It tells the reader to pause and see who is responsible. You are shifting the spotlight from the person to the result. This is very common in news reports or when describing historical events.

1. 1Building this structure is like following a recipe. You need four main ingredients. Follow these steps to get it right every time:
2. 2Start with the Subject: This is the person or thing receiving the action. A carta (The letter).
3. 3Add the Verb ser: Conjugate it to match your subject and tense. foi (was).
4. 4Add the Past Participle: This must match the subject in gender and number. escrita (written).
5. 5Add the Agent: Use por (or its contractions pelo, pela, pelos, pelas) followed by the doer. pelo João (by João).
6. 6Result: A carta foi escrita pelo João. (The letter was written by João.)

Use the passive voice with an agent when the result is more important than the person. Imagine you are in a job interview. You want to highlight a project. You might say, "This project was developed by me." In Portuguese: Este projeto foi desenvolvido por mim. It sounds professional and humble at the same time. Use it when reporting news. "The law was approved by the Senate." A lei foi aprovada pelo Senado. It is also perfect for art and literature. "The book was written by Machado de Assis." O livro foi escrito por Machado de Assis. It provides a formal, objective tone that is essential for B2 learners. Yes, even native speakers use this to sound more authoritative in meetings!

Do not use this for every sentence. If you do, you will sound like a very boring textbook. In casual conversation with friends, the active voice is much better. For example, don't say "The beer was drunk by me." A cerveja foi bebida por mim. That is just weird. Just say "I drank the beer." Eu bebi a cerveja. Avoid the passive voice when the action is simple and the doer is obvious. If you are asking for directions, keep it active. "Where do I find the bus?" is better than "By whom is the bus found?" Grammar is a tool, not a cage. Use it when it adds value, not just because you can.

One big mistake is forgetting agreement. The past participle must match the subject, not the agent. If you say As casas foram construído pelo homem, you are wrong. It should be construídas because casas is feminine and plural. Another mistake is using the wrong preposition. Some learners try to use de or com. Stick to por and its variations. Also, watch out for the verb ser. Some people try to use estar. While estar can show a state, the true passive voice for actions uses ser. Don't worry, even advanced learners trip over these sometimes. Just keep practicing!

How is this different from the "Se" passive? The se passive (e.g., Aluga-se casa) is used when we don't know or don't care who the agent is. It is anonymous. The passive with an agent is the opposite. It specifically names the doer. Think of it this way: Vende-se pão (Bread is sold - we don't care who sells it). O pão foi vendido pelo padeiro (The bread was sold by the baker - we want to credit the baker). Also, compare it to the active voice. Active voice is direct and fast. Passive voice with an agent is slower and more formal. It is like the difference between a sprint and a slow walk through a gallery.