If you have a basic knowledge of German, it is very interesting to choose a new college German, which is close to life. If you have a basic knowledge of German, it may be a little difficult to start with the second book, and there is no special emphasis on grammar, so many times you will not know how to understand and sort long sentences.
In addition, I think there are some good textbooks, which I recommend to you by the way.
1. There seem to be four schritte series published in Germany. Learning German from schritte 1 at first is really the foundation; The disadvantage is that it is too basic. I didn't feel any progress after learning four books.
2. My school now uses German: Na klar! It is also very suitable for people with zero foundation and a little foundation, and the word grammar is very detailed; The disadvantage is that it is more expensive.
I have a certain foundation. I bought 234 new college German books and read them when I have time. I think it's ok. I mainly want to broaden my vocabulary, and because I don't like grammar, I practice a sense of language, and the new version is very authentic.
Welcome questions!