"There were twenty-one men here."
Translation:Bylo tady dvacet jedna mužů.
It's also confusing for speakers of other Slavic languages, because only Czech and Slovenian (and Slovak marginally) have this "German quirk". My Macedonian boyfriend learned very good Czech very quickly, but whenever someone said, e.g. "Je mu šestačtyřicet let (He's 46 years old)", he would immediately hear it as 64 and he couldn't get his head around it.
(šestačtyřicet = čtyřicet šest)
(čtyřiašedesát = šedesát čtyři)
When doing math at school, only the "proper" forms (dvacet jedna) are generally used.
"Byl tady dvacet jeden muž." is also a correct translation we accept, but it is not something you have to learn. It is a less-used alternative.
Duolingo always shows the answer that is deems to be the closest and it does not care about the relative frequency of use in the spoken or written language.
No, it is not colloquial. It is rather obsolete in fact.
So there are multiple ways how you can connect a number and a noun if the last number is less than five:
dvacet jeden muž, dvacet jedna žena, dvacet jedno dítě; dvacet dva muži, dvacet dvě ženy, dvacet dvě děti
dvacet jedna/dva mužů, žen, dětí
jednadvacet/dvaadvacet mužů, žen, dětí
So in the first one you care about the grammar rules for the last number 1 to 4 and you use the nominative or accusative. But it is obsolete, I never use this actively. It sounds somewhat unnatural, I think it may be more common in administrative texts.
In the other two you use genitive.
Ok, I guess the rules I think I know don't always apply. I had thought that once you get to 5 of something, that you start using the genitive of the thing in question in both accusative and nominative.
Vidím jeden strom. Vidím dva (tři, čtyři) stromy. Vidím pět (a víc) stromů. (mužů, žen, koček, aut, etc)
I know I don't have to learn the other form, but out of curiosity, would that way of speaking be considered colloquial? I'm sure I sometimes also get confused with the subtle differences between Slovak and Czech as well. I am not even fully fluent in Slovak (married to a Slovak for 15 years), which helps to complicate my transition to Czech. Just wondering for future reference.