"All horses have a tail."
Translation:Alle paarden hebben een staart.
Does the Dutch rendition imply that the various horses are sharing a single tail, or is it clear that each horse has its own tail?
What would we say if all of the horses had one tail between them?
I think that it's the same phrase. If you wanted to emphasize that you meant each horse had it's own tail, and that they didn't share just one, I think you'd say:
Alle paarden hebben elk een staart.
I've seen elk(e) (each) used this way.
It's the same as with the English words "all" and "every". "iedere" is only used with singular nouns, but the meaning is most of the time the same.
"Ieder paard heeft een staart." (that rhymes!) - "Every horse has a tail."
When I got the above translation from English to Dutch wrong, it told me a correct word for horses was "knollen" ("Alle knollen hebben een staart" is the correction they gave). Google translate told me this means "tubers". Is this an error or is there an explanation for this?
Knollen can have multiple meanings, one of which being horse (paard): http://vandale.nl/gratis-woordenboek/nederlands/betekenis/knol
However, knol is not used as often as paard, and is generally only used for older horses.