This dissertation provides some insights into the process of Second Language Acquisition and how two opposing teaching methods can favor this process. The first one is the Natural Approach supported by Stephen Krashen, which poses five hypotheses for language acquisition to keep in mind. Even though all of the hypotheses are important, it is a good idea to draw attention to the comprehensible input, the optimal input, and the affective filter because any of them can lead to a successful or failing class. The second one is the Audiolingual method, which more dynamic and effective communicative...