It is best to study in that country. If there are no conditions, you have to rely on your own efforts. In the final analysis, language is used for communication, and the biggest obstacle is that there is no language environment for communication to improve actual communication and dialogue. After two and a half years in Korea, I worked hard myself. I was forced to do it when I was in the third grade, and after I graduated from the sixth grade, I could only exchange my life.