In fact, the contents of music theory books are similar, and there is nothing officially recommended. However, I can recommend a book on music theory to the landlord. I feel particularly good when preparing for the art exam in China. The "Basic Music Theory Teaching Practice Course" published by the Central Conservatory of Music with a red cover is rich in content and practical. Exercise books can use Song Xueyi's Music Theory Exercise Collection and the white cover of Communication University of China Press. The music theory of Nakagawa's recording department is very simple, and the focus of the exam is actually common sense, so prepare more. The two books I recommend are enough to prepare for the recording of biographies. I wish you success ~ ~