"Kupiłeś już to!" - why not?
Why does "Pani już to kupiła" count as wrong?
Unfortunately the course lacks the formal versions in a very big number of sentences. They were not provided at the beginning, and to add them everywhere now would be very hard and time-consuming. Of course we add them when requested. So added.
This one appeared in the "Formal you" section, that's why I was surprised it didn't work.
Oh. That's bad. But it's actually a sentence from "Verbs: Past Perfect", so this is one of the times when the algorithm randomly shows you some old sentence.
Same in the German course. Pure guesswork which translation to choose for the English "you".
No guesswork required, as all nine versions of you are accepted. I can't speak for the German course, though.
Please? Can't I put the object 'to' at the end?
Pronouns at the end rarely are natural. Not here for sure.
"You have bought THIS again!"
In my opinion ... if you want to emphasize the person, you can also say "Ty już tego kupiłeś/-aś". It counted as wrong though.
It's indeed wrong. Kupić requires the accusative, but tego is genitive.