Translation - Greek-French - Όταν πιάνουν ενα πουλάκι,ωραία του τραγουδούν?

Je ne comprends pas la langue-source, mais je comprends pas ce qui est tapé dans la langue-cible non plus, ce qui est plus embêtant...car c'est ma langue maternelle!
I don't understand the source-language, but I can't understand the target-language either, which is more annoying...as it is my mother-tongue!

aussi, si tu veux utiliser la forme interrogative en français, chrysso91, il faut inverser verbe et sujet : "Lui chantent-ils bien?" Mais on n'utilise pas "chanter" avec "lui", sauf si on ajoute un complèment d'objet direct, exemple : "lui chantent-ils une chanson". Et pour un oiseau, on utilisera plutôt le verbe "siffler", avec un complèment d'objet direct également, exemple : "lui sifflent-ils un air?", ou "lui siffle-t'on un air?".
Then, if you wanna use interrogative form into French, Chrysso91, you've got to invert subject and verb : "Lui chantent-ils bien"? But (we French) do not use "chanter" with "lui" except if there is a complement(object), E.G. : "lui chantent-ils une chanson?". Then, for a bird, it's more appropriate to use the verb "siffler", using a complement as wwell, E.G. "Lui sifflent-ils un air", or "Lui siffle-t'on un air?"
I think I'll edit the French text the way I told you, because I think you respected the meaning, just the way you expressed it wasn't understandable to a French native speaker...
I'll use "on", more general and better to be read as well.

I just figure out I forgot to translate "nicely", or "nice", so as "air" doesn't fit with "joli", I'll use the French term "mélodie" (which is feminine, so that it has to be "jolie" instead of "joli"-nice-)

à mon avis, et à y bien réfléchir, cette traduction aurait plus de sens si elle portait sur une question concernant la capture des oiseaux, en formulant ainsi : "pour attraper un oiseau, lui siffle-t'on une jolie mélodie?"
Mais cela correspond-il maintenant au texte original?

I think that your opinions are right and more than welcome Franky5591! It's true that, althought i got the meaning, it was hard to express it in french. Anyway, about your last question... No, changing it into "pour attraper un oiseau, lui siffle-t'on une jolie mélodie?" we miss the real point. The text has an ironic sense. It means that when we have a real chance, we make the most of it, we don't just throw it away...