In the online game Travian, the following sentence is used:
Your barracks is finished. A good step towards world domination.
Shouldn’t it instead be:
- Your barracks are finished.
- Your barrack is finished.
"Barracks" can be either singular or plural.
Plural in the context of "one barrack, two barracks," etc.
But "barracks" could also refer to a COMPLEX of military installations. In that case, "your barracks is finished," means "your military complex is finished," singular.
Yes, it's "computergamese."
No, oddly enough, barracks is a singular as well as a plural. Barrack exists, but only in barrack block, one constituent of a barracks, or metaphorical contexts such as 'a gloomy barrack of a place'. And many computer games allow you to put a Barracks (and, e.g. a Temple) in each of your cities: I would think "Your Barracks are finished" would mean you have one in each city, similar to "Your Temples are finished".
In United States Army usage a barracks is one building. It is equipped with beds, wall lockers, footlockers and a latrine, or bathroom, but not dining facilities. Soldiers live there. One building, a barracks usually housing one platoon of soldiers, is never called a barrack.