Does time always have to be specified to use preterite?
I'm still trying to wrap my head around preterite vs imperfect. Pretirite, as I understand is actions that have been completed with a specific time like ; esta manana yo comí cereales. While imperfect is actions over time, yo jugaba futbol cuando era nino, correct?
But if someone asks me what I did on the weekend, do I use imperfect or preterit?If I wanted to say, I watched movies, do I use Yo ví o yo veía peliculas? Because the weekend is over, so the action I did is over, but I don't specify when I watched and finished them on the weekend.
Another example, if someone asks me if I ate the cake they gave me as a gift, do I use comí or comía? Because I could have ate the cake over a period of time since I last saw this person, but the action is completed because I've ate it, so is it preterit or imperfect? These are probably stupid questions but I'm trying to learn.
7 Answers
Esta mañana comí pasteles.
Este fin de semana vi películas.
Cuando era niño comía pasteles.
Cuando era niño veía películas los fines de semana.
Sí, el fin de semana comí el pastel que me regalaste.
Cuando estudiaba en la universidad comía pasteles de vez en cuando.
Saludos!
To add to your confusion, I suggest : ¿Has comido//probado el pastel que te dimos? ( have you eaten the cake that we gave you?)
As for last weekend, normally preterite, although, if part of a story, rambling thoughts etc. it can be in the imperfect.. Sorry, no help, it still confuses me a lot. If it is background information, then the imperfect, but if it was the main happening, then preterite. Does that help?

I watched movies = yo vi = completed defined action I was watching movies = yo veia = continuing action in the past
Example: I was studying (continuing, so imperfect) when my phone rang (preterite - it rang, and then it was done).
Comi - I ate it and now it's finished/completed. Comia - I was in the act of eating it. I am referring to the past action as it was occuring, not defining its beginning and end.
Not stupid questions at all. It's great that you're trying to learn. Hope this little bit helps.
More examples - what tense? For the past few minutes, I was replying to your questions. When I saw your question, I replied right away.
You would use preterite because if you used imperfect you would have to add to the sentence. For example: Veía una película cuando mi amigo tocó la puerta.
I want to clarify something about some sentences I have read in this thread.
The sentence Esta mañana yo comí cereales is not common in Spain. When the action is finished in the past we don't use *preterito perfecto** always. Its use or not depends of when the action was. If we are talking about something near in the past (as the example above) we say:
Esta mañana he comido cereales
If we used este, esta, etc.., we use the present perfect (in Spanish preterito perfecto compuesto). So:
Este mes he ido al cine tres veces
El mes pasado fuí al cine tres veces
Or using my first example
Esta mañana he comido cereales
El jueves por la mañana comí cereales
This looks like not important but it is a way to express the distance (in time) of the action. For example, if I ask to anybody ¿Que has desayunado? He/She just understand that I'm asking about today. If I ask him/her ¿Que desayunaste?, he/she probably will ask me ¿Cuando?.
PD: As i said at the start of the post, this is the Spanish way, I don't know it is in South America.
PD2: I know that it is difficult for the non native Spanish speakers to avoid using the pronoums (yo, tu, el, ...) but a native speaker almost always omit them in any sentence.
welcome to the forum. Can you add your l evel of Spanish and English to your profile as it is helpful when deciding how to reply to a question or assessing an answer. It helps too, if you add whether you are female or male as in Spanish adjectives can change.
Finally, if neither Spanish nor English are your mother tongue it can help if we know what is. For example there are many brilliant people who use the forum who are learning both languages and who have a background where their native language use a different alphabet and grammar eg Arabic,Hindi Mandarin.
Imperfect is used to set the scene and for descriptions. It describes what you used to do. It is a more continuous timeline than the preterite.
In your first example of what you ate this morning in Spain they would use a third tense the perfecto - he comido.
As you referred to 'what I did on the weekend' which is the American way of speaking I assume you want to know about grammar in Latin America.
Here is an old song by Serrat about childhood. He uses a mix of preterite and imperfect listen and work out why he uses the tenses. He has an accent from Spain but sings slowly and clearly.
To all those who answered this thread
Are you happy?
Still no SD profile information nor any word of thanks for your efforts.