# "Tiu fadeno estas unu metron longa."

June 7, 2015

## 13 CommentsThis discussion is locked.

Why is 'metron' in the accusative?

The accusative is used when talking about distance or length. https://www.duolingo.com/skill/eo/Numbers

Then why is "longa" not in the accusative. The link demonstrates this, but doesn't explain why.

Like other sentences that contain "estas", there is no accusative direct object "-n". "Metron" takes the -n simply because -n is used with measurement. "-N" is used for a few other purposes that are not related to Direct Objects. Measurement is one of those other purposes.
According to Bertilo Wennergren (member of Academy of Esperanto): "The typical role of the accusative is to mark the direct object, but accusative has other uses too. That's standard terminology. "Accusative" is the name of a case. Cases have various uses.

"Somehow the idea that only N for direct object can be called "accusative" has spread a lot. It's however not correct." https://www.facebook.com/groups/duolingo.esperanto.learners/permalink/564207133741308/?comment_id=564211870407501&comment_tracking=%7B%22tn%22%3A%22R2%22%7D

I forgot to add that, personally, I have never seen a logical explanation as to exactly why a unit of measure would need to marked with an "-n". I do understand the logic of marking direct objects, and surely there must be some logic explaining the marking of measurements.

Perhaps it stems from Latin usage; see https://la.wikipedia.org/wiki/Accusativus#Accusativus_mensurae

However, it needs further evidence to state whether this usage of accusative in Esperanto was herited from Latin.

Thanks!

Same in German (der Mann ist einen Meter gross), never understood why.

Could I say "Tiu fadeno havas unu metron da longeco"?

It would make sense... so why not! (Except, "longo" means length - "longeco" roughly meaning "the quality of being long" so is for remarking rather than measuring.)

The voice is saying "unu metrono longa" or is it just me?

I put in "That thread is one meter" snd Duo is like "Nu. You forgot the long."