romanian language uses most letters...so you should pronunce all letters in the alfabet
also there are some groups of letters that need a specific pronunciation, for example
ci- you should read it like chi( the chi gong of chinese martial arts)
chi- you should read it like KI
che- read it KE
S with a coma under it ( i dont have at the moment the romanian letter sistem on my keyboard)- read it SHH
T with a coma under it, read it like TZ
All the rest of letters you speak normaly, similar to italian , or spanish