[inspiredworlds]

I'd tend to agree with CPops. If you have a reason to learn it will motivate you. If you have clients in that country or if you are intending to travel to a place, it will give you incentive to learn.

I might be a bit biased, but I'd go with Mandarin Chinese! A lot of people speak this language :)

I'm also the founder of a company called Native Tongue which creates vocabulary apps. It's one of the most simple ways to learn and fun to, so I'd invite you to try out our apps. Go to nativetongue.com and check out our mobile apps. If you have any questions, email me on hello at nativetongue dot com.

Thanks,

Matt