I just finished Greek with Rosetta Stone, so I'm delighted I can keep it active here. Thank you for putting all that work into it! I am please that the keyboard Rosetta Stone provided is the same as the regular Greek keyboard, since I got pretty good at it. (This was not the same with the Russian keyboard, unfortunately.)
However there are some spelling differences, including άνδρας instead of άντρας, and αδερφός instead of αδελφός, which is what is in my phone multilingual dictionary and another Greek course I have (Living Language). Are these dialect differences, spelling change differences or are both versions acceptable?
Άνδρας and αδελφός are the "original" one (from ancient Greek), however in modern Greek there are some versions of these and others words as well (δέντρο/δένδρο, γιατρός/ιατρός, εφτά/επτά, οχτώ/οκτώ, etc.). There is no correct option, both versions are right, you can use whichever you like the most.
P.S. You will often see words with νδ also written with ντ. This happens because in ancient Greek δ was pronounced /d/ and not /ð/, like nowadays. So νδ made a /nd/ sound, which survived in modern Greek in the form of ντ (which is now pronounced /d/ or /nd/, varying on the region of Greece). Hope I helped!
Thank you! I'd figured out the nt, mp things. I've also noticed that some speakers pronounce the spelled nasal and some not. It's sort of interesting that Rosettastone is using the more colloquial version. Since Philadelphia is the "city of brotherly love", I could guess that adelfós must be the older one.