Hello manu, Both are correct! The 'key' about the difference is the Ancient Greek.(two vowels would be "merged" into one, longer vowel. In modern Greek things have been simplified in terms of both pronunciation and conjugation but some things have been retained.) You will see it propably in other verbs like Συζητάω and Συζητώ or Περπατάω or Περπατώ. Hope it was clear :)