这里的 “the book” 指的是规则手册、法律或行业准则。形容一个人做事非常严谨，严格遵守所有程序，不通融、不走捷径。

• The police officer did everything by the book during the investigation. ^{那名警官在调查过程中完全照章办事。}
• He is a very strict manager who likes to do things by the book. ^{他是一个非常严厉的经理，喜欢按规矩办事。}
• To avoid any legal issues, we must handle this by the book. ^{为了避免法律问题，我们必须严格遵守程序。}