by the book

prep_phrase

(idiomatic) In a manner which adheres strictly to rules, legal requirements, or official procedures.

He always follows the rules by the book.

意味（1）

(idiomatic) In a manner which adheres strictly to rules, legal requirements, or official procedures.

As far as he is concerned, he umpired by the book.

意味（2）

(idiomatic, by extension) In a manner which appears too studied, ritualized, and therefore artificial.

Romeo: Sin from thy lips? O trespass sweetly urged!

Give me my sin again.

They kiss again.

Juliet: You kiss by th' book.