You should learn russian, because it is very interesting language. If you learn this language you will be more clever than you can. Лучше учить русский язык, потому что он очень интересный. если ты учишь этот язык ты будешь более умнее
You can think, that if you speak English, you can communicate with everyone. So, do you know that in Russia lots of people don't speak English? Russia is a very interesting country, it is big enough to have many only-Russian speakers. If you want to visit Russia, you should learn how to speak there