Ponyboy spoke good Latin, Johnny was from Cherokee and Mexican decent, Dally was born in Poland,  Darry took French in high school, and Steve was from Brazil, so when they were mad at eachother, this is what happened:

Ponyboy: rants in Latin

Johnny: rants in Cherokee/Spanish

Dally: rants in Polish

Darry: rants in French

Steve: rants inPortuguese

Soda and Two-bit: sit there confused/rant in English