Why not "ти їш яблука"?
Because there's no "їш" in Ukrainian. The correct second person singular form of їсти is їси
in parts of Ukraine (namely the West) people don't say їси and think it is a weird form
What do they say instead ?
They say їш!
In the far west (Canada) we use їш
Well, it just isn't correct. "Їш" looks like calque from Russian "ешь".
Off course! An apple a day keeps the doctor away:) Хто яблуко кожен день з'їдає, той у лікаря не буває!
what's the difference between яблука and яблукя?
яблукя is not correct. There's no such word.
Shouldn't this be accusative case? ie Ти їси яблуку?
It is accusative. яблуку is dative
Is it not яблуки for plural 'apples'