\"Hi! Korean 2A Workbook\" is a textbook that can be used together with the âHi! Korean 2A Studentâs Bookâ in class or for self-study. You can review content step by step, from replacement exercises to expanded practice, using the grammar you learn in the textbook. In the Self-Evaluation section at the end of each unit, answer questions about the vocabulary and grammar youâve learned to confirm your degree of understanding.