Translation:What kinds do I want to paint, beautiful ones or small ones?
They haven't seemed to make that feature available yet. Of course, it would be very tedious to slow down the tousands of recordings they have. They may not add it.
Unfortunately, Hungarians speak very quickly because of how long some of their words can be, so it is difficult for beginners to understand.
I disagree. As Ryagon said, while it may not come up in conversation, its similar to things you would mutter or think to yourself: your preparing to paint, and are trying to decide how much time and effort you are planning to put in: are you just gonna paint a small picture real quick, or take your time to make a nice picture?
This course does not use a computer voice (which can pronounce any sentence at any speed), but instead they got a live person to record a bunch of sentences -- I think between 3000 and 4000 was a number I saw once.
Even that is not all the sentences of the course; if they had recorded each sentence twice (once in normal speed, once more slowly), they could only have done about half the number of sentences.
So we have a more natural pronunciation but no slow voice.
I'm not sure about the outcome but okay, indeed it's possible technically. I'm "afraid" by the time you would do this for yourself, you could just get used to the normal speed. After all, certain TTS tasks are simply not worth slowing down because it's still just bad. Here you can listen to actual speech...
Nearly all courses on Duolingo (e.g. English, German, Italian, Spanish) use a computer voice (text-to-speech synthesis).
So there was no recording involved; they just told the TTS engine to read a given sentence at two different speeds. And they can tell the TTS to read three hundred new sentences without having to pay a voice actor any more money.
I don't think anyone would ever use that sentence in real life.
Imagine an artist standing in front of her empty canvas and thinking about what to do. She knows she wants to paint a picture with many hearts in it, but she's uncertain which kind of hearts she would rather like to paint right now. Many many very small ones? Or some that are a bit larger but prettier?
The main point was that you can do adjective plural accusatives, including interrogative words. As time passes, I'm less and less convinced this is really worth "teaching" in a Duolingo course aiming for the basics - for simple adjectives, maybe it is, for "milyen", most probably not. It's more important that by the end of a course, someone should develop a feel for what is possible within the language and what is completely alien to it.