Specifying the numeral "One" is written "Ein" ??? Why not "Eins Apfel" ?
Yes, it's "ein Apfel". "eins Apfel" is wrong.
What is wrong with "Einen Apfel"? Why can't we say that?
It's fine. Just be aware that "ein Apfel" is nominative and "einen Apfel" is accusative.
Could you please explain what do you mean by Nominative and Accusative? I feel these might be important concepts of language for me to learn in order to advance further on in a better way. Thanks in advance!
So it's "Ein Apfel", right? It's not accusative in this case. The solution says it heard "Einen Apfel" and marked it correct...
Either is fine.
It shouldn't though, because "One apple." is nominative. Or am I missing something?
It can be either.
Was liegt auf dem Tisch? - Ein Apfel.
Wie viele Äpfel möchten Sie haben? - Einen Apfel.