This is a well-organized presentation of the content necessary to prepare for various tests to certify Korean language proficiency.
Although it was originally prepared for the purpose of being a lecture for undergraduate students at university, I thought it would be good if the general public could also study on their own, so I added a considerable amount of practice problems to make it suitable for self-study as well.

Korean language proficiency refers to the ability to use the Korean language, and it refers to the ability to correctly and accurately express one's thoughts and feelings using the Korean language, as well as the ability to properly understand the thoughts and feelings of others.
Broadly speaking, in terms of expression, there are speaking and writing skills, and in terms of understanding, there are listening and reading skills.
This book uses these four areas of language proficiency as a framework to provide a clear overview of the basic concepts and knowledge necessary to develop language proficiency in each area. It also presents practical exercises related to these areas.