Originally Posted by
corkpunter
Mandarin, Hindi and Arabic would be my guess. Ofcourse English and Spanish will still be very important, I just think those 3 will have a much higher profile in 100 years.
I wouldn't discount Russian either, if it's population size stabilises! Mind You despite, the prominence of the Japanese economically since the 1950s, Japanese never became a hugely significant world language, also it's probably the hardest to learn of all the languages mentioned
Ride them on the beaches!