"De quoi parlions-nous ?" is continuous and expresses that there was one single conversation topic.
The answer to this question would, therefore, be about one thing only.
"De quoi avons-nous parlé ?" is past and complete as well, but it may cover a list of topics.
In English, you would need other elements of language to distinguish these meanings if you used a past simple in both cases.
So I took a break from Duolingo, came back a year later, and naturally typed the exact same thing in again for the exact same answer... I'm having some trouble understanding your explanation, here, as in my understanding there simply isn't a difference between "what were we talking about" and "what did we talk about" in English in terms of usage. Either could mean multiple topics, or one, as "what" isn't necessarily numerically limited. I understand that you're saying the sentences are different in French, but in terms of the English translation, is what you're trying to say that you've chosen the corresponding phrases arbitrarily to make a point about the difference in the French (kind of like "road" vs "street" for "route" vs "rue", except with less dictionary justification) or that there's a nuance in the English that I'm missing?
there is a difference in English in terms of usage and context.
You would probably use a past continuous tense if the sentence adds other elements of language, like "we were talking about that yesterday... when something happened".
In French, you don't need an interruption in the middle of a continuous action to use an imperfect.
From the French sentence "we talked about that yesterday", the action is necessarily past and complete (with "yesterday") and therefore you have to pick the tense which expresses past and complete actions, a compound past: "nous avons parlé de ça hier".
Sorry Sitesurf....I'm with Nathan. You are imagining a difference in English which just isn't there. The difference is real and important in French as you no doubt want to teach. Your argument above applies to the French certainly but not the English. I appreciate it is hard with the format limitations of DL to always test what you want....so I'm quite sympathetic!
We are teaching tenses one by one in dedicated units. This one is devoted to the French imperfect, which can translate to various English tenses depending on 1) the French meaning, and 2) the more appropriate English tense that will back translate to the original French tense.
"to talk" is a dynamic verb, which enables us to make a better match than with stative verbs.
A dynamic verb in simple past must (back) translate to a French passé composé, as long as no other element of language points to something different than a past, one-time and complete action.
"Hier, nous parlions..." is different from "Hier, nous avons parlé...": the first one implies one topic discussed at length, and the second one suggests either one short topic or several topics tackled with no reference to the length of the conversation.
"Yesterday, we were speaking..." is the best translation for the first meaning.
"Yesterday, we talked..." is the best translation for the second meaning.
That is the "less bad" we can do to evidence that French and English past tenses do not map.
I really cannot see any difference between :
"What did we talk about yesterday" and
"What were we talking about yesterday".
I have read all the posts in this discussion several times but am still no clearer.
Is there a simple way to explain this french tense and it's rules? I really need help with this one!
Me too... This point of grammar seems definitly very hard, with the context on the one hand and dynamic verb or not on the other hand... My god... And you know I can add one thing : in French Passé composé and Imparfait are very different, that's right. But here, with this example, one can say "Nous avons parlé de quoi hier" or "Nous parlions de quoi hier", it makes no difference. Perhaps a very little one : "Parlions" is better to use if you want to restart the conversation. But once again it is very subtil and not as different as DL seems to say.
I am not exactly sure what duolingo is trying to accomplish anymore. Are we seeking to communicate in French or are we seeking a degree in French grammer. I do not believe that in normal English communication we would differentiate between "what did you do" and "what were you doing" although i understand the subtle differences highlighted more in French.
"What did we speak about yesterday" was my answer and "What were we talking about yesterday" was provided by DL as the correct answer. The only difference seems to be the use of "speak" and "talking" which mean the same thing in this instance. I believe my answer points to a single subject in the way it appears to have been aimed. I have read all of the previous comments and feel my answer addresses this question. What am I missing here?
With the past imperfect "parlions-nous", the sentence refers to one topic which was debated at length. Otherwise, for several, briefly discussed topics, the passé composé would be used "avons-nous parlé". This is why "were we talking/speaking" has been prefered to "did we talk/speak".
I don't understand why in a previous exercise I translated this tense with the continuous and it should have been with 'did', whereas in the current exercise with the same tense in French, the translation to English is wrong with 'did', but not with the continuous? (I asked my question as well at that exercise, but I saw no answer, therefore I'm trying it here)