because the weather in Russia is so cold ！

Because you don't know this language...)))))) For us all that we don't know seem so difficult))

I don't know. Not only Russian is difficult.

Yes, Russian is very difficult for study, but it's very beautiful language. In my opinion French is more difficult. All languages is difficult cause we begin to study something new

It depends a lot on language differences. Russian might be hard for people whose native languages are Indian, Wolof, Tibetan, or any other language that is not Slavic. However, people who speak languages such as Belorussian, Ukrainian, Czech, Serbo-Croat, Polish, and other Slavic languages will have an advantage, though it might still be hard. I have also heard that Latvian has several similarities to Russian, and I have noticed similarities between French and Russian (as well as Spanish and Russian). They are European languages though, so this might be expected.