Preterite vs Imperfect Usage

At its core, the distinction is about perspective. It’s not just about *when* something happened, but *how* you see it.

• The Preterite (Pretérito Perfeito) is for completed actions. It’s a snapshot. A photo. It has a clear beginning and a clear end. You did it, it’s over, move on. Example: Ontem eu comi uma pizza (Yesterday I ate a pizza).
• The Imperfect (Pretérito Imperfeito) is for ongoing actions or descriptions. It’s a video. A habit. It’s what was happening when something else interrupted. It also describes states of being, feelings, and the "status quo" of the past. Example: Eu comia pizza toda sexta (I used to eat pizza every Friday).

Think of the Preterite as a point on a timeline and the Imperfect as a wavy line or a blurry background. When you combine them, the Imperfect provides the context, and the Preterite provides the events.

1. 1You need to know your endings for both. Luckily, they are quite regular!
2. 2Preterite (Regular Verbs):
3. 3-AR (e.g., falar): falei, falou, falamos, falaram.
4. 4-ER (e.g., comer): comi, comeu, comemos, comeram.
5. 5-IR (e.g., abrir): abri, abriu, abrimos, abriram.
6. 6Imperfect (Regular Verbs):
7. 7-AR (e.g., falar): falava, falava, falávamos, falavam.
8. 8-ER / -IR (e.g., comer, abrir): comia, comia, comíamos, comiam.
9. 9Yes, the -ER and -IR verbs share the same endings in the Imperfect! That’s a small gift from the grammar gods. Note that the "you/he/she" form and the "I" form are identical in the Imperfect, so context (or using pronouns like eu or você) is your best friend here.

Use the Preterite for:

• Specific, completed actions: Ele comprou um carro novo (He bought a new car).
• Actions with a defined time frame: Eu morei em Lisboa por dois anos (I lived in Lisbon for two years).
• A sequence of events: Acordei, tomei café e saí (I woke up, drank coffee, and left).
• The interruption: O telefone tocou (The phone rang).

Use the Imperfect for:

• Habits and routines: Antigamente, eu corria todos os dias (In the past, I used to run every day).
• Descriptions (Age, Weather, Time, Feelings): Fazia sol e eu tinha dez anos (It was sunny and I was ten years old).
• Ongoing actions (the background): Eu estava estudando quando... (I was studying when...).
• Polite requests: Eu queria um café, por favor (I would like a coffee, please—literally "I was wanting").

Don't use the Preterite if you are describing a state that didn't necessarily "end" at a specific moment. For example, if you say Eu estive triste, it sounds like a very sudden, contained medical condition of sadness. Usually, you’d say Eu estava triste because feelings are the "background music" of your life.

Conversely, don't use the Imperfect for a specific list of actions. If you tell a boss Eu chegava atrasado ontem, you’re saying you "used to arrive late yesterday," which makes no sense. You should say Eu cheguei atrasado (I arrived late).

Also, avoid using the Imperfect for the main event of a story. If the hero saves the day, he salvou the day (Preterite), he didn't salvava it (Imperfect), unless saving the day was his mundane 9-to-5 job.

One of the biggest hurdles is using the Preterite for habits. In English, we say "I went to that park every day." A learner might say Eu fui ao parque todos os dias. While understandable, a Brazilian or Portuguese person will think, "Wait, did you go for a specific limited time, or was it a habit?" Use Eu ia for habits.

Another classic is with the verb ser (to be).

• ✗ Ontem o tempo foi bom.
• ✓ Ontem o tempo estava bom.

Using the Preterite with weather feels like the weather was a completed project. Stick to the Imperfect (estava / fazia) for the "vibe" of the day.

Mixing up the meanings of certain verbs is also common. Some verbs change their translation depending on the tense! For example, conhecer in the Preterite means "to meet (for the first time)," while in the Imperfect it means "to know/be familiar with."

Let's compare these two in the same scenario: a job interview.

• Preterite: Eu trabalhei na Google. (I worked at Google—period. It's a fact on my resume.)
• Imperfect: Eu trabalhava na Google quando decidi sair. (I was working at Google when I decided to leave. It sets the scene for the decision.)

In English, we have "I used to," "I would," and "I was doing." Portuguese bundles all of these into the Imperfect. This is actually a simplification! You don't need a different construction for "I used to play" vs. "I was playing." Both can often be Eu jogava.

However, watch out for the "interrupting" sentence:

Eu dormia (Imperfect) quando o gato pulou (Preterite) na cama.

The Imperfect is the long, continuous action (sleeping), and the Preterite is the sudden event (the cat jumping). If you use Preterite for both, it sounds like: "I slept and then the cat jumped." The nuance of "while" is lost.