I agree; it is very contrived. One could argue the viability of the sentence, supposing we were just speaking about this butter that was ordered from a delivery company, for example... but it's more likely a native speaker would simply refer to it as "the butter."
I can conceive of someone saying 'this taxi you ordered is not here yet', which under some unusual circumstances could be whittled down to 'this taxi is not here'; but in the case of butter, it's difficult to imagine it ever being said.
The sentence could also work if the speaker were brandishing a photograph or drawing of a particular piece of butter, or as a philosophical assertion that runs contrary to the evidence of the senses about some real piece of butter. However, all of these scenarios seem too ridiculous (particularly about butter) for the sentence to have any value.
But there are sentences without a nominative, such as У меня нет брата "I have no brother", but more literally, "at me (is) no brother" -- the "I" is the complement of a preposition and is in the genitive, and so I suppose the subject is "no brother" -- which is also in the genitive here since the brother is absent.
I suspect that the genitive when talking about the absence of something has some of a partitive quality to it. Eg. "I do not have butter" in Russian is said something like "There is none of the butter with me" - it's not really absent; in a sense we're really talking about quantities.
There's nothing of that in this sentence; we're saying that some object is not here.
Does it sound right?
"This butter is not here". That is some broken-ass English if I've ever seen any.
This seems to be a common misconception about Duolingo - it is not about the sentences you learn, rather the vocabulary and sentence structures that make up those sentences. You may never say this particular sentence, but it doesn't matter, as the majority of the sentences you use in every day life have never been uttered before. Therefore, what Duolingo tries to do is teach you these sentence structures and vocabulary, which your brain can then repurpose into new constructions — hence better teaching you the language.
PS: just because you would never say something does not make it "not proper English". It's grammatically correct, and so "proper English", no matter how contrived.
I get you on the first paragraph. I will try and keep that in mind when I shake my head at some of the funny sentences. But I am still standing by my opinion that "this butter is not here" is partially nonsensical in English. And you wouldn't say it. There are people using this whose first language is not English. Why have them think that this sentence translation is OK?
i don't think this is or should be the philosophy of duolingo. it is very possible and proper to teach us the vocabulary and sentence structures that characterize the language without along the way training us in unnatural constructions that don't occur in the language. that is counterproductive.
I agree., I would much prefer that all the sentences not only be grammatically correct, but also semantically correct.
The classic example of a sentence that is grammatically correct but not semantically correct is "Colorless green ideas sleep furiously" (Noam Chomsky. Google it for a complete discussion).
I am sure that there are many native English speakers here who would be willing to be alpha testers and point out problems like this.
I agree with @AmisticaRMA, DL should put a bit more effort in providing sentences we would USE in real life. All that you've argued here can be understood/accepted, but still it would be all much more useful, if all the same done using useful sentences. Then we have 2in1: learning grammar + useful phrases, don't we?
In this sentence, it seems to me (and I may be wrong, I'm just as much a learner as you) that "there is no butter here" is not semantically correct because this sentence, as demonstrated in the use of "это", places emphasis on a specific portion of butter (ie "the butter" not just butter in general).
Nominative: «Масло не здесь.»=“The butter's not here.”; «Она не здесь.»=“She's not here.”.
Genitive (specifically, partitive): «Масла нет здесь.»=“There's no butter here.”; «Её нет здесь.»=(literally)“There's no her here.”. The latter sounds a bit odd in English —recall Gertrude Stein's jarring line “There's no there there.”— but English does use the partitive comparably in, for example, “I want none of her!”. In the current context, English offers periphrastic partitive constructions such as “There's no sign|trace of her here.”.