And another thing... Most Serbians, Bulgarians, Greeks during the Ottoman rule did understand some Turkish, but not anymore. The Ottoman empire did annihilate a very large part of the Christian population on the Balkans and it had the power to exterminate them completely or to convert them forcefully into muslims, but it didn;t have any interest in doing so, since Christians paid much higher taxes than muslims and also paid devisherme.