Okay, It's very technical, grammatically, and possibly not very interesting as a result -- but here goes.
Brian initially writes "Romani eunt domus" which the Centurion "translates" as "People called Romani they go the house."
He gets Brian to change it to "Romanes Ite Domum." which is correct for "Romans go home."
But at one point, Brian originally says that the Accusative is required for "Domus" ~ at which point the Roman Centurion pulls out his sword, until Brian squeaks "Locative"... or something.
To use the Locative form would in fact mean "at home", so while the revised Latin is correct, for movement towards it is better to use the Accusative. [Domum= to home.]
Brian did get the grammar right at this point, but the Centurion insisted that he was wrong.
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