Learn a language in only 10 days

Trying to learn too many words at first can actually slow the language retention process. However, once this “core vocabulary” is mastered and used consistently, it provides a framework for accelerated language learning. The Pimsleur Approach aims each lesson at teaching you to use the core vocabulary of the language, so you can speak the most in the least amount of time. It's not how many words you know, but rather, which words you can use.

http://tehrantimes.com/index.php/science/2471-how-you-can-learn-a-language-in-only-10-days