Textbook 1+ 1, which is recommended by many teachers now. The textbook 1+ 1 is a full-color teaching aid with comprehensive knowledge points, good induction and clear organization, which is very suitable for self-study. You can check for leaks and fill gaps, but you can't tell the teacher the knowledge points. Read a book by yourself and do some exercises later. The topic is very new. Listening to the teacher is easier to understand. If you want to buy workbooks, there are books that meet the standards during teaching, which is the standard training for each class, and each chapter has standard volumes. You can also buy textbooks that match the textbook 1+ 1.