I did, too...and i really think that, in these cases, both should be accepted since the verb is the same. In a conversation, we would be able to ask questions or understand from the context which one it was; there is no real way to do that here. This is not the first time this has happened. In going back to listen, I couldn't really tell that it was 'er' instead of 'ihr'.
If you use both forms in a sentence, it can be like this:
"Mein Hund trinkt meinen Tee."
Hund is nominative and Tee is accusative. Notice that "Tee" is masculine. If the accusative is a masculine noun, "meinen" is used.
It is "meine" if the accusative is a feminine noun: "Mein Hund trinkt meine Milch." and it is "mein" for a neuter noun: "Mein Hund trinkt mein Wasser."
I am confused. I come from a Latin background, in which there is the Genetive case for possession. In German, is "meinen" the Accusative? Because it describes the condition of the direct object? Is there no distinction between possessive pronouns and accusative pronouns when they describe the direct object? Please help!
Because the word Tee is masculine (der Tee) and it's the direct object of trinkt here.
So you need the masculine accusative form meinen.
mein would be masculine nominative (e.g. Mein Tee ist kalt "my tea is cold", where "my tea" is the subject) or neuter accusative (e.g. Er trinkt mein Wasser).
meine would be nominative or accusative for either a feminine word or for a plural word: Er trinkt meine Limonade; Er trinkt meine Getränke.