Let's start learning foreign languages. At present, the level of teachers in training field is uneven, and many people make mistakes. As for your worry that you can't keep up, in my experience, foreign languages are slow and it is impossible to digest and absorb them thoroughly in class. As long as the teacher is right, as long as you take good notes, you can review it slowly in the future, which is also rare information. I say this because my former Korean teacher graduated from Wu Da University and went to Korea for further study for two years. I think he speaks very well. Compared with other teachers I have heard, he is less prone to make mistakes. Of course, it does not rule out that there are good teachers in other places, and good quality and low price also exist. However, for foreign language beginners, it is difficult to distinguish between good teachers and bad teachers. So let's find a safe place first.