It is commonly taught that the imperfect is used to describe general facts and habitual or recurring actions in the past. But what about sentences with the adverbs 'siempre' and 'nunca' and the peculiar cases of verbs like 'saber' and 'poder'? Which of the following sentences is correct and why? Perhaps there are some native speakers here, who would also like to comment.
- Nunca supe qué tenía mi abuelo. / Nunca sabía qué tenía mi abuelo.
- Siempre supe quién era. / Siempre sabía quién era.
- Ella nunca pudo resolver sus problemas. / Ella nunca podía resolver sus problemas.
- Siempre jugó con su hermano./ Siempre jugaba con su hermano.
From what I have learnt, I would say that 'nunca' warrants the preterite since it states that an action never took place. On the other hand, one could also make the point that it is a statement of a general fact?
I would also say that 'siempre' denotes a general state or a habitual action, which then would require the use of the imperfect. It does not specify a specific point in time or demark the end of an action in the past.
So, I would say that the correct sentences would be the following.
- Nunca supe qué tenía mi abuelo.
- Siempre sabía quién era.
- Ella nunca pudo resolver sus problemas.
- Siempre jugaba con su hermano.
But what do you say? My choice here is based upon what I have learnt so far. But I am unsure of whether it is correct and whether the reasons I gave are correct.