Yes, the book signature can be written according to personal preferences and needs. Generally speaking, it can include the following content:

1. First, name or pen name: you can write your real name Or a pseudonym used in a book.

2. Secondly, date: you can write the date when the bookmark was made or the date when the bookmark was used.

3. Finally, quotation: You can write your favorite sentence or famous aphorisms from the book, etc., to express your emotions and feelings.