This sentence is not anything a native speaker of English would say. Is "the unanswered one" supposed to refer to unrequited love?
I suggest you put the sentence in in whatever language the metaphor belongs to, and leave it to someone to translate it into appropriate English.

If you change "...love when lemons..." to "...love, while lemons...", then it should be fine, IMO. Grammatically.

Of course it'd be nicer to have some translations so as to have a clue to the meaning, but otherwise it's fine.

Why is there an @delete tag?

@witbrock: A native speaker could say all kinds of things. It's more of a question of whether or not a native speaker would say that kind of thing in the specified context, but we don't know the context here, and so cannot judge.

> we don't know the context here, and so cannot judge.

I'm generally in favour of the 'imagine the context' school of sentence interpretation. But I don't think this is a good example. 'for the unanswered one' is particularly awkward.

Google returns about 26,400 with ‘"unanswered love"’ [1]. It’s a negligible number compared to 619,000 hits for ‘"unrequited love"’ [2], but I do doubt all these 26 thousand cases are written by Russians. :o

[1] http://www.google.com/search?cl...4b02364fbbaa34
[2] http://www.google.com/search?hl...4b02364fbbaa34

It's the /one/ that makes it unnatural.

I can write a program that will generate syntactically correct but nonsensical strings of English. It doesn't seem to me that they would be suitable for helping people to learn how to produce natural communications. I can't imagine a thought that this sentence might be trying to express for which this would be the mode of expression chosen by a native speaker.

My best guess is that it's supposed to mean something like "oranges symbolise a happy love, and lemons an unrequited one"

> It's the /one/ that makes it unnatural.

If you replace "one" with "love", it would make for repetitive prose.

> 'for the unanswered one' is particularly awkward.

It's not awkward but poetic.

> If you replace "one" with "love", it would make for repetitive prose.

Take out the 'the' and it's perfectly natural (except for the oranges and lemons stuff).

"Oranges mean happy love while lemons are for unrequited love."

> It's not awkward but poetic.

It's not poetic, it's confusing. 'one' isn't a natural way to refer to love in that statement. 'sort' would be a bit clearer.

"Oranges mean happy love while lemons are for the unrequited sort." ( '... of love' is omitted)

> "Oranges mean happy love while lemons are for the unrequited sort." ( '... of love' is omitted)

That's more eloquent, but I disagree that it's in any way more "correct". I can see the current one as being a sentence in, say, a romance novel.

It seems to me that the pedagogical virtues of isolated fragments of allegedly poetical writing may be overestimated.

If I were attempting to teach someone French, I should not start with Rimbaud. And this is by no means Rimbaud.

There are pedagogical criteria in Tatoeba?

Any poem that included this sentence would be spoilt by the fact that it's obviously mistaken English rather than poetic English. 'One' fails to refer back to anything because 'love', the only candidate, is used in an uncountable sense earlier in the sentence.
'Happy' v 'unanswered' could, at a stretch, be used poetically for two possible kinds of love - but when what is said is that they're symbolised respectively by oranges and lemons it's either too trite to merit that level of innovation or awkward because the non-standard terminology gets in the way of the meaning.

I'm on the side of the people who think this sentence should be changed, which makes the count 4 to 1. It's a shame we can't reach a consensus, but we certainly have a clear majority. Removing the "@needs native check" tag (by now, it has been checked by plenty of natives) and adding "@change", which I will do after two weeks unless the original poster shows up or someone else gets to it first.

I have to say, though, in re-reading the comments, that there is some rather lovely English prose in them. Perhaps some of it could be added to the sentence base. The comments also might be taken to serve as some sort of weak (but insufficient) evidence of the stimulative, and hence, arguably slightly poetical nature of the original "sentence".

Im my opinion, "unanswered" is not for poetics here, but as literal translation from Russian. In Russian it's a common word. It should be changed if it's not common in English.