Yeah, I guess so. Polish wiktionary shows three meanings:
showing that the author of the sentence is not sure about whether it's true, but he thinks that it probably is
showing that the author of the sentence is not sure about some decision, but he thinks that he probably will decide on that after all
showing that the author of the sentence is not sure about some opinion, but he thinks that he can probably agree
I believe we would use "ona jest mała" for small.
Many languages have overlaps between small, short (height), short (length) but I think Polish is quite clear in this regard.
Mały (small) Niski (short height eg. a person) Krotki (short length eg. a spoon)
Not sure about a building though. Maybe a version of niski too?
What version of those 4 adjectives have you written above?
By version I mean in this list order:
Eg... Zajęty (m), zajęta (f), zajęte (n), zajęci (mpp) zajęte (n-mpp)
They look like (mpp) to me but when I google-translate "tall man" and "tall men", the adjective doesnt seem to change :-/
All adjectives used by DPan76 are masculine singular (so they do not exactly fit "osoba" (a person) or "droga" (a road).
Their 'mpp' (masculine personal plural) variants would be: "krótcy", "dłudzy", "niscy" and "wysocy". Due to the meaning, "krótcy" and "dłudzy" are forms that may exist in a declension table but they wouldn't really be used, because people have height, not length.
I think it's really weird to use a personal pronoun in Nominative (on the other hand, in other cases it's unavoidable) to denote something else than a person. Maaaybe an animal. So we should stay with "short" here.
Like, imagine we're talking about a lamp. "To jest lampa. Ona jest mała." - that sounds pretty weird. I'd definitely omit the pronoun and say "To jest lampa. Jest mała."
No, I don't think there is, it's still a form of "niski", like about a short person.
Let's look at the image here: (https://meble-bik.pl/pol_pl_Komplet-mebli-do-salonu-Denver-14194_1.jpg) - the piece of furniture with the TV, at least compared to that one on the left (I'd probably call them both 'szafka' but I'm not sure what English would use), is "niska".
About your shelf example... doesn't it mean that someone hung that shelf too low from the floor, so it's not about the shelf's size, but rather where it's located? That would use an adverb: "Tamta półka jest za nisko".
Yes in English, the cabinet (or 'TV stand') below the TV will be called 'short' compared to the 'tall' one on the side.
My question about the shelf being too low might be understood as the opposite of 'high'
Eg.. That shelf is too high, I can't reach the things on it. That shelf is too low, cleaning it hurts my back.
That painting on the wall is nice, but its a bit high. No I think its a bit too low.
Do you think the dogs will jump over the wall, or it's high enough? No they will escape, the wall is too low.
That last example has an overlap with 'short' and we could use 'high/short' but the first two don't.
Anyway, maybe this is getting too advanced for this early stage. I'm sure I'll get understood for now. Esp. with hand gestures haha.
Main thing is not to pick up bad habits which are hard to rectify later.
If you don't see a slow speak button (I haven't used the app in ages), that sounds like a question for the Troubleshooting subforum (https://forum.duolingo.com/topic/647) or the Duolingo subforum (https://forum.duolingo.com/topic/1). No one here is able to help you with that, we can only help with language-related things.