main book

例句：

1. 1.The main book on the subject is in this volume.
   这本关于这个主题的主要书籍在这个卷册里。
2. 2. He spent most of his time reading the main book.
   他花大部分时间阅读主要书籍。
3. 3.The main book was published last year.
   主要书籍去年出版。