This is the funny thing. My language has acusative case but its nearly impossible to explain it in English in a way that it makes sense.
Basically its a change in certain words (nouns, ajdectives, pronouns) in a specific cases. English used to have them too, one of the few remaning ones are I and ME. You say “I see two red doors” but “you see me”. Acusative cases is used for object (the language category) connected to a verb. E.g. you always use “see” with something, that something that you see is acusative.
In German you often use acusative in connection to specific prepositions, such as bis, durch, ohne, durch, für etc.
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