The difference is in intonation. Here, qué has a more strong intonation than que. I have recorded an audio in a web page. The first phrase is with qué and the second one with que.
I appreciate the audio examples. But they sound practically identical! Being only barely able to distinguish these (and I seem to have a pretty good ear for subtleties in spoken language), I'm having difficulty imagining how, if hearing only one of them, one would ever be able to discern just from the audio which was actually meant - especially given the variability in how people intonate identical words.
I would hear the sentence with "qué" as "what they ate" (like an embedded question ... "What did they eat?" "I don't know what they ate") while "lo que" is "the stuff that they ate." And I don't know that you'd ever say the latter. Maybe if you meant "I don't know the names of the stuff that they ate, I saw it but it's some foreign food."
Not "ustedes", but "you all" in English is what I am saying is not accepted but in only some areas of the US. It should just be "you". Yes, I am aware that "vosotros" is used more in Spain and "ustedes" is used for both formal and informal in the Americas, kind of like "you" which is used instead of "thee" and "thou" for informal as well as for formal.
Allintolearning, I agree that we USA Southerners have a very GOOD plural version of "you," mostly for casual use, and think it's a very practical way both to shorten "You all" and to be inclusive of a group. But every case of using "you all" does not have to be casual or idiomatic. For example, "I cooked a big meal just an hour ago, and everyone ate heartily. Why are you all asking for more food now?" The cook emphasizes in that case the whole group, or more than two, probably, want more food, which would not be clear otherwise. Using "you" alone could sound like you're just calling one person a glutton, and if it did happen to be just two people, the cook may have said, "... why are (just) you two asking for more food now?" And, of course, we use that helpful contraction that lots of folks make fun of us for - "y'all." While it's not accepted in formal writing, it IS quite polite to be inclusive, when we say, "Y'all come back to see us!" ;-)
That is great that you explained your dialect, but in other parts of the country. We would simply say "Why are you asking for more food now?" and unless we specified one person's name or stared at one individual, it would be considered plural. If we really added the word "all", we would say "Why are all of you asking for more food now? Didn't I serve enough?" and in Spanish they would use "todos de ustedes". Actually asking why people would want more food is something I would not usually do unless those people were family or friends, though. That whole scenario is actually a familiar way of talking that is perhaps common in the South. I would simply make more food.
allintolearning, thanks for your reply to my commentary about our informal Southern USA "plural form of you," often contracted to "y'all." (I see, now that I'm on the computer instead of the phone app I usually use, that the discussion was a year old!) When I gave the scenario of a cook asking why the people she fed were back in an hour asking for more food, I was thinking of a bunch of kids, who perhaps did not eat well at dinner time - especially their vegetables! - but then they came into the kitchen bothering the cook for more of the parts they liked -- not that we would question guests as to why they asked for more food - HA! But I can think of many common uses of "you all" that are perfectly grammatically correct. Think of a teacher telling her class, "The Governor is coming to our class, and we will all be on TV while he talks about the importance of education. You all must be quiet and on your best behavior while he is here." In both of her sentences, the teacher could have omitted using "all" entirely, but was using it for emphasis. When someone is speaking to a group, even adults, it is very common to hear "you all," and not just in the regional South. (I have lived in many places in the USA.) "You ALL know the importance of guarding your passwords!" "You ALL must adhere to dress code and facial hair restrictions to work at Disney World." And, "God bless you all!" I don't know where you're from, by the way, but certainly admire your dedication to language skills!
I should actually have been marked wrong on this (can't believe I'm saying so) because que with or without an accent makes a big difference to the translation I think: instead of I can't say what they ate (with an accent) it reads I can't say that they ate (without an accent).
The first is a statement and the latter is a question, though if you stuck the latter on the end of DL's sentence it wouldn't make any sense unless you put it in quotes like:
I cannot say "What did they eat?" // No puedo decir "Qué comieron?"
But that's not how the DL sentence is phrased and even then you're more likely to use a verb like 'preguntar' than 'decir'. Hope this helps!
This is gramatically incorrect. A change in subject, the use of 'que', and the expression of doubt requires the subjunctive tense. Such as "No puedo decir que coman" in thr present or "No pude decir que comieran" in past subjunctive. Dont give bad habits to new Spanish speakers, please. When you can, avoid que to connect two subjects!