Learning another language enables me to meet outstanding people from another part of the world who made me realize how ignorant I am, thus making it possible for me to expand my horizons as I always get something new that I've never heard before by talking with them.

Link of discution:

http://www.italki.com/discussion/71832

1st. Mandarin - million in 1051 - China, Malaysia and Taiwan.
2nd. Hindi - 565 million - India, north and central regions.
3rd. English - 545 million - U.S., UK, parts of Oceania.
4th. Spanish - 450 million - Spain and the Americas.
5th. Arabic - 246 million - Middle East, Arabia, North Africa.
6th. Portuguese - 218 million - Brazil, Portugal, Angola.
7th. Bengali - 171 million - Bangladesh, Northeast India.
8th. Russian - 145 million - Russia and Central Asia.
9th. French - 130 million - France, Canada, West and Central Africa.
10th. Japanese - 127 million - Japan

Yes learning a language is very important but learn just for learn without love ins't my style, for learn one language we need feel, love and be intersted and focus...

Mandarin just have a lot of speakers because they have a lot of population...French can be useful but for me ins't one of most importants, and is easy to learn is similar with portuguese in grammar....

I speak some languages: English (school), Spanish (HOME), Portuguese (HOME), French (HOME) and German (Because I live in Germany), ones better than anothers and now I want learn Russian/Ukranian for personal reasons...

(I put here I learn, some I learned in school anothers in home and another because I change country)

Taras I really liked your answer 

Ok, it's very interesting question. For example know Ukrainian and Russian. Because i know russian I have many acquaintances in former USSR - for example Kazakhstan, Russia, Belarus etc. We can understand each other, and speak for anything... But world so big, and so different... And other world more goodness and friendly, than many country ex USSR :) It's hard to say.. In English ) I like open new horison, and meeting new friends.. just do it. I try to know English, because it is language for international use ( it understand in world-wide ). Maybe in future (when i'll know English ) I will start to learn some any languages - spanish or arabic... Language it's not only tool of career or travelling.. I like just do it. It is life, and we have so little Time..So.. I think - language - it is a key to World. We must find it. P.S Excuse me for my English. Good luck to you !