The only way that I know of to learn a language quickly is to move to that country and never speak your native tongue. In other words, force yourself to speak everything in the new language now matter how bad you are at it. Aside from this, I don't think you can learn a language quickly.

I think learning many foreign languages is very difficult but nobody says that it is impossible. I have heard that some languages have similar vocabulary or gramma like Spanish, Portugess or Italian or another example: Spanish and French have common gramma; so it would be easier to learn foreign language if they belong to the same language family. Of course, @desertjedi is right....force yourself to speak is the most important but I also understand that some poeple aren't breave enough. So, good luck :)

It is not possible unless you are very gifted at languages.