How do I know it's not "Produkuję krzesła"? I can sometimes tell the difference between "e" and "ę," but to my ears, there's no difference in how the e is pronounced in 1st person singular and 3rd person singular.
(C.f., the "ę" in "mężczyzna," which sounds very much like an "ę" rather than an "e")
you cannot tell the difference, because we pronounce ę very slightly or say "e". Ovrpronouncing "ę" is wrog, saying "e" is not. And I think duolingo TTS never says "ę" at the end of verb
http://www.polskieradio.pl/9/305/Artykul/275142,Wymowa-e about 2.22 there examples of pronounciation of ę 2 good 1 bad,
That was interesting, although I wouldn't necessarily worry about ambiguity. The spoken language tends to be less demanding in that respect, since you also have context or can clarify if asked to. Just think about Mandarin Chinese: possibly a large part of why they did not convert their writing system into something easier is because of large degree of homonymity, and yet they somehow function with all of that when talking to each other. Similarly, that distinction in Polish can be often deducted from context, or it doesn't matter, or the sentence can be rephrased in advance, or clarified if needed.
Hearing this slight „ę” at the end might be tricky and even then not all speakers would use it. Therefore it's a good idea to learn recognizing it from context.
I think it is as much of a sentence as the Polish, as far as the subject being unclear.
-Does your friend produce chairs or fix the machines at the factory?
Are you telling me that the Polish produkuje is any clearer on the subject of the sentence? How did they get "he" for the translation? Couldn't it be just as easily "she"? Or "it," as in a manufacturing machine?
In the most basic sense, the difference between to and ono is like between "this" and "it" respectively.
The pronoun ono is much rarer in Polish that its equivalent in English, because the subject has to be the neuter gender first (and inanimate objects in Polish are not limited to being neuter)… and even then Polish has a tendency to drop pronouns.
Personally I use it to clarify the subject of a sentence inside a larger paragraph, especially if it differs most from the other contenders by its gender. I prefer writing such sentences as VSO. I'll show you on a real example from my wiki:
„Lightning Dust decyduje się na użycie tornada, by odstawić konkurencję w tyle. Niestety wymyka się ono spod kontroli i balon, w którym lecą główne bohaterki, jest w niebezpieczeństwie.”
Here „ono” makes it clear, that the second sentence is about neuter tornado, not a feminine „konkurencja” (competition).
Also, like the other pronouns, it may be added to emphasize the subject stronger.
„Kryształowe Serce?! Ono jest moje!”
In situations when you could "this" instead of "it", Poles prefer the former. So typical simple sentences with „być”, and especially the verbless ones, would use „to”.
I understand that it's implied by context. Without context, however, this sentence doesn't make sense that the translation is "he" unless you point at the male person while speaking. In this case, it would be the same in English--context can imply a subject, otherwise you have to point at somebody hahaha
This is a complicated matter. Yes, of course English can generally use it. The problem is, such a construction doesn't exist in Polish. You can't use "oni" or "one" in such a situation. And if we accepted "they" for 3rd person singular... we'd have no way of knowing if the user consciously used singular 'they' or if they just made a mistake and didn't understand the Polish sentence. True, no subject is specified here, but the learner has to realize that this is 3rd person singular. Therefore we decided not to accept it. Frankly, the number of users asking for it is a lot lower than I would expect.
"Produkuje krzesła" is strictly taken out from the context. It matches perfectly correct: he/on, she/ona, it/to,ono, but also kid/dziecko. Ex. 'dziecko produkuje krzesła'. A: What does he/she/it/kid/father/mother/wife/brother/....doing? B: Produkuje krzesła./Produces chairs.
It isn't there. In Polish you can drop personal pronouns, even in third person, but in third person it creates ambiguous sentences. That's why Duolingo accepts (or at least is supposed to accept) both "he" and "she" as valid translations. Normally it would be clear from the context who you are talking about.
In short, no. "Stool" is "stołek" or "taboret", and "armchair" is "fotel".
Krzesło is a furniture with a backrest that is generally designed for sitting at a table or a desk. They are lightweight or on wheels so that you can easily move them a little when you want to get seated, though in some special circumstances (like at hairdresser) they may be screwed into the floor permanently.
If it is heavy, more comfortable, and generally something you put in your living room, then it is "fotel". Car chairs are also "fotel", but can also be called "siedzenie". Extra car seats for little children is "fotelik".
I hope my answer was comprehensive enough.