"Que" in asking questions

I seem to come across various ways of using “que” in sentences asking “what,” for instance:

O que é que aprendeste?
O que aprendeste?
Tu aprendeste o quê?

So, what is the difference - could all be correct? Because the system seems to prefer a particular sentence structure for some examples, but not others…

I am not seeing an answer from the natives yet. I think they all mean the same for us estrangeiros

But there are some subtle differences in meaning between the second example and the other two. I think when tou use ‘é que’ it might add a little more emphasis. It also can affect the grammar but I don’t remember the details

@hnturnbow, “é que” is a fixed element that we can optionally add to questions without affecting their meaning. Just an idiomatic thing we do, as explained in this Learning Note: É que in Portuguese Questions | Practice Portuguese

So, O que é que aprendeste? and O que aprendeste? are perfectly interchangeable, but the former would probably be the default choice in conversational language for most people. This é que is not inherently more emphatic.

Tu aprendeste o quê? is just as correct and can also be considered interchangeable in meaning, but not always in emphasis. We’re simply moving the word que to the end of the sentence (and that’s why it gets an extra accent on top), but depending on the speaker’s tone of voice, we might perceive it as an expression of surprise or uncertainty, e.g. “You learned WHAT?!” (surprise/shock) or “You learned what, exactly? Can you repeat?” (uncertainty).

The answer of Chat GPT (a great program!)

The three Portuguese sentences are similar, but they have slightly different nuances. I will explain them individually:
1. O que é que aprendeste?
• Literally: “What is it that you have learned?”
• Very common in Portugal, standard language.
• The emphasis is on “what”, i.e. the question about the content of what was learned.
2. O que aprendeste?
• Literally: “What did you learn?”
• Shorter, more direct, often used in everyday language.
• Basically means the same as the first sentence, but sounds a little less formal.
3. Tu aprendeste o quê?
• Literally: “Did you learn something?”
• Colloquial, often used to express surprise or to ask for clarification when something is not understood or when astonished.
• Emphasis is strongly on “o quê” (what), it sounds like a question or a slightly surprised “Excuse me?”

:white_check_mark: Conclusion: All three sentences ask about what has been learned, but the tone, formality and emphasis differ:
• 1 = neutral/formal
• 2 = neutral/colloquial
• 3 = informal, surprised or probing

What do you think about it?

@behr.erlensee, it’s workable, needing some adjustments. All of the sentences are informal, and if anything, #2 (“O que aprendeste?”) is actually the least casual-sounding between them. All of them also have the same basic translation (there’s no ‘something’ in #3).