Thanks for your report. Unfortunately, we cannot change the Greek sentence because the tree is locked! Εσύ ευχαριστείς is accepted as alternative, but we can't add it as the best translation at the monent ;)
As about Εσύ ευχαριστάς, it is not wrong, but is used mainly in dialectic forms of the Greek language and therefore it would be much better to be an alternative sentence.
Is "ευχαριστήθηκες" used to mean "you enjoyed/ are satisfied" only in the past tense? I've also usually heard it phrased as a question, particularly after a good meal. :) This is not exactly about this particular question (unless the "enjoy" translation applies to present tense too), but I'm just curious.
These are two different verbs. Morphologically, they are the active and passive voice of the same root, but they have different meanings.
- Ευχαριστώ means "thank".
- Ευχαριστιέμαι means "enjoy / be satisfied" as you said, and it does not mean "be thanked".
"Ευχαριστήθηκες" is the 2nd singular person of the simple past tense of ευχαριστιέμαι (you enjoyed / are satisfied). In the present tense, it would be "ευχαριστιέσαι" (you enjoy / are satisfied). The same forms of the other verb are "ευχαρίστησες" (you thanked) and "ευχαριστείς" (and not ευχαριστάς, you thank).