"Annī urnen!"

Translation: I see a horse!

[ThoricWeevil]

Annī is plural, isn't it?

[Ctxkh1Me]

Anne "horse" is annī in both the singular and plural accusative cases. So when you see annī, it could be plural or singular, unless the presence of modifiers (kostōbe annī "strong horse" vs kostōbī annī "strong horses") or contextual information offers greater specificity. This is true for a number of other nouns, e.g. zaldrīzes "dragon" which becomes zaldrīzī in the singular or plural accusative.