The verb saber (to know) belongs to the "strong" preterite family -- the same group as ter (tive), poder (pude), and fazer (fiz). Its stem changes completely from sab- to soub-, and it carries a crucial meaning shift: while sei means "I know" (a state), soube means "I found out" (a punctual event). This shift catches many learners off guard and is one of the most important things to master at the B1 level.
Conjugation
| Person | Form | English |
|---|---|---|
| eu | soube | I found out |
| tu | soubeste | you found out |
| ele / ela / você | soube | he/she found out; you found out |
| nós | soubemos | we found out |
| (vós) | (soubestes) | (you all found out) |
| eles / elas / vocês | souberam | they found out; you all found out |
The stem soub- replaces sab- throughout the paradigm. The endings follow the strong preterite set: -e, -este, -e, -emos, (-estes), -eram -- the same endings found on ter (tive, tiveste, teve...) and poder (pude, pudeste, pôde...). Notice that the eu and ele/você forms are identical: both are soube. This also happens with querer (quis/quis) but not with ter (tive/teve) or poder (pude/pôde).
The meaning shift -- "found out", not "knew"
This is the single most important thing about saber in the preterite. Like poder and querer, the preterite of saber does not simply place the present meaning into the past. It changes the meaning itself:
| Tense | Form | Meaning | Type |
|---|---|---|---|
| present | sei | I know | ongoing state of knowledge |
| preterite | soube | I found out / I learned | punctual moment of discovery |
The preterite captures the moment of acquiring knowledge -- the instant you learned or discovered something. It does not describe a state of knowing.
Soube que ele estava doente.
I found out (that) he was sick.
Quando é que soubeste?
When did you find out?
This is not optional nuance -- it is the core meaning. "Soube que ele estava doente" means "I found out he was sick", not "I knew he was sick." Getting this wrong changes the entire sentence.
Core uses
Finding out news or information
Soube da notícia ontem.
I found out the news yesterday.
Soubeste o que aconteceu?
Did you find out what happened?
Discovering the truth
Quando soubemos a verdade, ficámos chocados.
When we found out the truth, we were shocked.
Negative -- never found out
Nunca soube a resposta.
I/He never found out the answer.
Eles nunca souberam o que se passou.
They never found out what happened.
Soube vs sabia -- preterite vs imperfect
This contrast is where the meaning shift becomes clearest. The preterite (soube) marks the moment of discovery; the imperfect (sabia) describes ongoing background knowledge.
| Form | Tense | Meaning | Example |
|---|---|---|---|
| soube | preterite | found out (punctual) | Soube que ela se ia casar. (I found out she was getting married.) |
| sabia | imperfect | knew (ongoing state) | Sabia que ela ia casar. (I knew she was going to get married.) |
| soube | preterite | found out (punctual) | Só soube ontem. (I only found out yesterday.) |
| sabia | imperfect | knew (background) | Eu já sabia. (I already knew.) |
Saber a (to taste) in the preterite
The verb saber also means "to taste" when followed by the preposition a. In the preterite, it uses exactly the same forms -- the context makes the meaning clear.
A sopa soube a alho.
The soup tasted of garlic.
O bolo soube bem.
The cake tasted good.
This usage is less common in the preterite than in the present (sabe bem, sabe a chocolate), but it appears whenever you are reporting how something tasted on a specific past occasion.
Common mistakes
1. Not recognizing the meaning shift. Translating soube as "I knew" instead of "I found out" is the most widespread error. The preterite of saber almost never means "I knew" -- that is the imperfect (sabia).
2. Using a regular ending. Forms like sabeu or sabi do not exist. The stem changes to soub- and the endings follow the strong preterite pattern, not the regular -er set.
3. Confusing soube with sabia. If you mean "I already knew that", you need sabia, not soube. If you mean "I just found out", you need soube, not sabia. The tense choice changes the meaning completely.
4. Forgetting that eu and ele are identical. Unlike ter (tive/teve) or poder (pude/pôde), both the first and third person singular of saber in the preterite are soube. Context and subject pronouns disambiguate: Eu soube vs Ele soube.
For the full preterite system, see Preterite Overview. For the present-tense forms of this verb, see Present Indicative of Saber. For another strong preterite with the same ending pattern, see Preterite of Poder.
Related Topics
- Pretérito Perfeito Simples OverviewA2 — The simple past tense for completed actions
- Preterite of PoderA2 — The verb poder in the preterite
- Preterite of TerA2 — The verb ter in the preterite
- Present Indicative of SaberA2 — The verb saber in the present tense
- Preterite of FazerA2 — The verb fazer in the preterite