"Trinkst du dein Bier nicht?"
Out of idle curiosity would another acceptable translation be "are you drinking your beer?". I know that we have two ways of presenting the present tense where as German only seems to use one
IE : "we are drinking beer" and "we drink beer" as apposed to deutscher "Wir trinken Bier".
Both English translations seem to always be acceptable for that one German sentence. Am I right in thinking that?
The two versions are not always accepted. IE for "Ich sehe das Brot", Duo acceped only "I see the bread" and not "I am seeing the bread" because "I am seeing" in English means "dating"...pretty odd to date a bread.
They are not always accepted, but I think it is more often than not a mistake on the grading algorithm's part. I think "see" as you use it is a special case, but you might be able to concoct an example where "I see" and I am seeing" are both correct.
It could work if one were asking brewers whether or not they drank their own product as a general question.
why it is dein Bier, not deinen Bier? i do not know when we should use Nom. and Dat.
It's accusative case because "dein Bier" is the direct object of the verb trinkst.