"I am not wearing a shirt."
Translation:Ik draag geen hemd.
Because replacing niet een by its abbreviation geen is not optional. Niet een is only used in the sense of not [even] one (in which case it's spelled niet één) or if you can't abbreviate it because for some reason een is bound strongly to something else, e.g. dit is niet een gans maar een eend (this is not a goose but a duck).
So would "Ik draag niet een hemd. Dat is een pak." be correct or wrong? Or in other words, is it a grammatical necessity to use "geen" or does it simply sound very weird if their is no good justification for it or you don't want to stress the "een" (which would then be closer to how it is in German, probably)?
Everything I wrote is based on German, since there seems to be little difference between the two languages in this respect.
I guess niet een is always grammatical, though it very often sounds weird. I think your example is wrong in this sense, i.e. it sounds weird. Niet een gans maar een eend should be about the limit of what can justify niet een.
While I also noticed that Dutch seems to be quite close to German in many instances, it does not necessarily follow from there that that's also the case here. But since google claims almost three million hits for "niet een" (not including "niet één" and compared to about 340 million for "geen"), we can suppose that it's at least in some cases grammatical, but also that "geen" is strongly favoured.
This article http://gagl.eldoc.ub.rug.nl/FILES/root/1999-43/02/GAGL-43-1999-02.pdf claims that "niet een" can be "OK when echoic, or contrastive", which sounds relatively similar to German (you may remember this discussion about "kein OR nicht [ein]" from some time ago: https://api.duolingo.com/comment/3195539), where "nicht ein" is often not wrong, in fact, even though here too "kein" is favoured in many cases. But this would also imply that "Ik draag niet een hemd." could be acceptable in the right context, since it can be contrastive (or echoic, for that matter) after all (e.g. as in the example I provided, even though there are examples imaginable where the contrast is stressed more strongly).
I am also not sure whether your claim in your first post that "niet een" is used "if you can't abbreviate it" is correct, with the example "Dit is niet een gans maar een eend.". At least in German I would say that "Das ist keine Gans, sondern eine Ente." is also possible (even though I personally would prefer "nicht eine" in this case), just less contrastive.
If some native speaker wants to chime in, you're very welcome to do so, but it now seems to me that there is indeed not too big a difference between Dutch and German in this case.
You are right about Gans/Ente. I expressed this so carelessly that it actually came out wrong, but what I (apparently) meant to say is that nicht eine Gans sondern eine Ente is about the limit of where you can use nicht ein. Sondern (English but, Dutch maar) is just about sufficient justification to make me not cringe when hearing such a sentence with the stress on nicht. With the stress on the first indefinite article it's fine anyway. And with the stress on Gans and Ente it's definitely not OK.
I like the article you cited. I had not heard of blocking, but that's definitely what's going on here. This allows me to explain why I am unsure whether to consider niet een / nicht ein grammatical. If we want to keep the grammar of a language simple and comprehensible, we must ignore blocking effects or describe them as such. But normally, grammar is described in terms that can't directly account for blocking. If we follow this tradition, we only have a choice between a grammar that claims niet een to be grammatical, and one that is overly complicated because of the unnatural workarounds for representing the effect of the blocking.
What you said is: I wear a shirt not. Or if taken grammatically correct: I don't wear this one shirt (since it's all smelly and stuff). Dutch is very close to German, I am German, therefore correct. (In German it'd be: Ich trage kein Hemd)
Also to point it out to all of you of non-germanic origin: Ik draag niet een hemd - Ich trage nicht ein Hemd. ( I wear not a shirt / I don't even carry one shirt.) (Wrong)
As I already explained, in your sentence the placement of niet is weird, resulting in the meaning "There is a shirt which I am not wearing." The correct placement would be between draag and een, but niet een must be replaced by geen, except in certain situations when you want to express an unusual meaning - especially when you want to negate een hemd rather than draag or the entire sentence.
It seems like it would translate to "I am wearing a shirt not," which when translated into a sentence that makes sense, would be just fine. The negation, like with some German sentences, comes at the end of the sentence to negate the statement that precedes it, and therefore makes sense.
As a German native speaker I can assure you that "Ich trage ein Hemd nicht" is by no means the normal negation of "Ich trage ein Hemd". It's what you could say if you were wearing all your shirts at the same time, except for one.
Normal negation happens directly after the main verb, not after the rest of the predicate (which is separated from the main verb and comes at the end of the sentence), and certainly not after the object where bzysh put it. So in German, the negation of "Ich trage ein Hemd" is "Ich trage nicht ein Hemd". But we can't leave the phrase "nicht ein" as it is unless we have a special meaning in mind in which the object is negated ("Ich trage nicht ein Hemd, sondern eine Hose"). Normally we have to replace it by kein: "Ich trage kein Hemd."
In Dutch these things work exactly the same way.
Because it translates literally to "I am wear no shirt". What is ben (am) doing there?
English is the only Germanic language in which the progressive is mandatory, so in Dutch you normally don't say the equivalent of "I am wearing no shirt". You can, if you want to stress the progressive aspect, but the Dutch progressive construction is a bit awkward: "Ik ben geen hemd aan het dragen." Literally it translates to "I am no shirt at the wearing".
The real issue is that in Dutch (like in my native German) it is obligatory to use geen (instead of niet een) when you can. You only avoid doing this to express something unusual. In the case of "Ik draag een hemd niet", I guess you are right after all and this sentence is grammatical, but then it most likely has the same meaning as the word-by-word translation to German: "There is a shirt which I am not wearing." (This is so far-fetched that at first I didn't think of it.)
It's technically correct, but in Dutch the progressive is normally only used when you want to stress the progressive nature. I guess this is even more true for transitive verbs, since for these the progressive construction feels even more clumsy.
- Usually I wear shirts, but today I am not wearing a shirt.
- Gewoonlijk draag ik hemden, maar vandaag draag ik geen hemd.
With the so called stative verbs, you can see the same principle at work in English. (Stative verbs include verbs of perception such as see, hear, know, think, like and other verbs such as have, need, own, sound. As a rule of thumb, a verb is static if it does not describe an action that people usually take by a conscious decision.) In Dutch this is a more general phenomenon affecting all verbs, because the progressive is not as well established in Dutch as in English.
- Usually I want sugar, but today I want salt. (Not: ... today I am wanting salt.)
- Gewoonlijk wil ik suiker, maar vandaag wil ik zout.
In some cases, such as for on-going deliberate actions, you can optionally use the progressive in Dutch, but even then you don't have to.
- Usually I go slowly, but today I run.
- Gewoonlijk gaa ik langzaam, maar vandaag ren ik.
- Usually I go slowly, but at the moment I am running.
- Gewoonlijk gaa ik langzaam, maar op het moment ren ik / ben ik aan het rennen.