"I am very tired."
Translation:Είμαι αρκετά κουρασμένος.
I am very tired = Είμαι πολύ κουρασμένος. _
I am quite tired = Eίμαι αρκετά κουρασμένος, unless you stress the word "tired," in which case it actually means "very tired," doesn't it?
I'm sure I've heard Greek friends say κατακουρασμένος. Would that also be correct?
The sentence can't be found in the incubator, so it must be a so-called "ghost sentence". But yes, "πολύ κουρασμένος"=κατακουρασμένος", it's nice because it's colloquial.
It's still marked wrong ... https://screenshots.firefox.com/7CEkHRjyjFuQ7ZPz/www.duolingo.com
It's still marked wrong because the sentence can't be found at all, so it cannot be edited. I just confirmed that you were right.