Well, Duolingo didn't like my τσίζκεϊκ (i.e. with diacritical marks, trema, διαλυτικά or whatever you call them), even though it seems to me that the officially accepted τσίζκεικ technically should be pronounced as TSEEZkeek (ει being pronounced as 'ee'). Googling around I found τσιζκεικ, τσιζ κέικ, τσιζκέικ, τσιζκέϊκ, τσιζκεϊκ, τσίζκεϊκ, τσισκεικ - you name it. My favorite is this article from the Greek Βικιπαίδεια called 'Τσίζκεϊκ' which begins with the sentence "Το τσιζκέικ (στα αγγλικά σημαίνει κέικ τυριού) είναι γλυκό που..." and later talks about "[την] μοντέρνα έκδοση του τσίζκέικ" (yes, with 2 accents). That's three different spellings in one article...
But what I like most about this Wikipedia article is that we learn that the cheesecake--"although considered to be an American sweet"--was actually first prepared in Ancient Greece, where it was called πλακούντας (the Wikipedia gives the Modern Greek version of the word - it would have been πλακοῦς in Ancient Greek). [Yes, that's 'placenta', but here we are talking just about a kind of flat pie (the Greek word is a distant relative of the English word 'plank' by the way). The French--who were probably just jealous of the Greeks inventing the cheesecake LOL--were supposedly the first to use this word in its modern anatomical sense.]
Of course we knew all along that Gus Portokalos was right, but for all you stubborn unbelievers of Big Fat Greek Cheesecake Supremacy, here is a quote from an article by Devra Ferst called The Great Cake Debate:
John Segreto, author of “Cheesecake Madness” (Simon Schuster, 1984), explains that the first cheesecake on record was created “between 800 to 700 BC in ancient Greece on the Island of Samos in the Aegean Sea.” The decadent food was fed to competitors in the first Olympic Games in 776 BCE, purportedly to fuel them with energy to compete. The treat soon became a wedding cake for the wealthy in ancient Greece, and trickled down to the common man by the time of the Roman Empire. Cheesecake, according to this lineage, spread throughout Europe under Julius Caesar’s reign.
TL;DR: I propose to accept the following sentence as an answer: Εσείς έχετε τον πλακούντα. (And maybe τσίζκεϊκ could be accepted, too?) ;-D
Thank you for your kind words. As ChrysiCh. says, as of now there seems to be no official Greek spelling. I checked Τεγόπουλος-Φυτράκης, Δ. Δημητράκου, and the Λεξικό Της Κοινής Νεοελληνικής and found no entries (of Μπαμπινιώτη I only have the Ετυμολογικό Λεξικό). So I never made an official report, not even the 'my translation should also be accepted' kind.
Well, you officially just ruined cheesecake for me! Anyway, since it's a foreign word that doesn't have an official translation (at least not yet), τσίζκεϊκ (which was my answer too), τσιζ-κέικ, τσιζκέικ (I'm not so sure about this one) should all be accepted, but τσίζκεικ certainly shouldn't.
P.S.: I'm a bit surprised you didn't find a τσίζκέΐκ too...
I really think it's wrong for Duolingo to be using words like cheesecake and sandwich for part of the core introduction to the Greek language. These are introduced words and have many different spellings in Greek, and do not help reinforce the true nature of the language. Yes, beginners do need to know that Greek has many introduced words, but Duolingo shouldn't be using them when trying to teach a different aspect of the language, in this case auxiliary verbs. It's very easy to be marked incorrect having got the verb right and the particular spelling of cheescake wrong.
Please change them out when you go from beta to "live"
Thanks for considering this, your hard work is greatly appreciated.
Other introduced words which you use a lot and could well be replaced by natural Greek are ketchup and biscuits(cookies). If you want to reinforce at every opportunity how Greek nouns change with gender and case , then introduced words don't really add a lot of value.
Plăcintă is a Romanian, Moldovan and Ukrainian traditional pastry resembling a thin, small round or square-shaped cake, usually filled with apples or a soft cheese such as Urdă. The word plăcintă comes from Latin placenta, which means cake, from the Greek plakount – "flat cake". (from Wikipedia)