Why is the twelfth month called December?

[talt]

I tried to translate the sentence
"why is the twelfth month called December" and it turned out like this:

cur mensis duodecimus december appello?

what do you reckon?

[Cinefactus]

'is called' must be passive, and it is third person, so you have the wrong form of appello.

[Keera]

Is "cur mensis duodecimus december appellatur?" better?

[Nikolaos]

Is "cur mensis duodecimus december appellatur?" better?

Yeah, that looks good to me.

[jeemkerry]

When the gregorian calendar came into effect, we added two months, but kept the names for the last four months, even though they no longer represented that number stage.

[scrabulista]

Actually we didn't add them (not at the time of Gregorian anyway); we shifted New Year's Day from March back to January. Under some conventions, March 24, 1731 would be followed by March 25, 1732.