Lots of people have tried to link Basque to Etruscan, African languages, Caucasian languages and so on, but most scholars see Basque as an isolated language. It was spoken long before the Romans brought Latin to the Iberian Peninsula. Palatalization? is quite typical of Basque, "tt" and "dd" are /t_j/ and /d_j/ respectively. "s", "z" and "x" are sibilants, the latter designates /S/, the first is apical and the second laminal. The function of stress in Basque is generally not understood. "j" is pronounced as [d_j], [S], [X], [j] or [Z] according to region. The vowel system is the same as Spanish for most speakers, namely /a, e, i, o, u/. Some speakers also have /y/.