To learn the language for a month really, but for that you have to fully immerse yourself in the language environment and to study not less than 4-8 hours a day. It is quite difficult and time-consuming way, not everyone has enough time and effort to devote to the language up to 8 hours a day. But in a month quite really to master the basics of grammar, learning to build simple sentences as well, depending on the capabilities of the person, to learn from six hundred to two thousand words. But this does not mean that you will perfectly understand foreign speech and speak perfectly this language. Subsequently have to constantly repeat the studied material and to learn new information.
The most important thing in learning a language is constant practice. Repetition will allow you passive vocabulary activate. If you want to master a foreign language, you will have to spend an average of two years. Advanced level require you to have about three thousand words and a full understanding of the grammar and constant practice in speaking and communicating with native speakers. Passive vocabulary can be obtain by reading books and articles in that language.
This, we can conclude that to acquire a basic level of the language you can for a month, but in the future will need to develop and learn in order to advance to a higher level.