People doesnt learn new language that fast, and its even more harder if it was a language in a completely different world with different culture and different species. I think he was barely in that world for a month and aside from the names, he had a hard time pronouncing other words by mimicking what he heard.
Fun fact:
It turns out that it takes 2,200 class hours to learn Mandarin for English speakers. If you put the rest of your life on hold and focused only on studying Chinese – at 5 hours of practice a day, it would take you 88 weeks.The tonal nature of the language makes speaking it very hard as well.
So yeah, if you're learning a new language that is vastly different from your native language that uses a completely different system, its hard.