That's not very surprising; he might want to do something about it in the future, but for now, it's fine.
"Hello, everyone! My name is Raafi, or you can call me Traveler if you prefer, I answer to both. I'm not usually a teacher and I'm doing this circle on a bit of short notice, so I don't expect to have enough of a language lesson to fill the entire period; do feel free to ask questions about the subject, and you can save any other questions you have for the end; I'll fill any extra time with a question-and-answer session. Let's get started."
It quickly becomes obvious that he's working from a lesson plan designed to get someone to the point of being minimally functional very quickly, rather than giving a comprehensive understanding of the language; he covers the grammar, but only in simple terms, and the vocabulary is mostly practical words that would be relevant to getting by in a new city. He explains some basic things about his world, too, mentioning gods and churches, explaining how to tell the difference between humans, elves, dwarves, gnomes, and halflings, and passing around examples of the gold, silver, and copper coins they use as currency.