by the book: In accordance with rules or regulations; Strictly following the rules or the official way of doing something; By following the official rules very strictly,according to the rules; in the prescribed or usual way.
As in My boss insists on doing everything by the book.
中文释义：by the book：By是根据的意思，book是书本的意思。By the book这个习惯用语的意思是循规蹈矩，照章办事。这个习惯用语里的book最初指的是圣经。十九世纪早期，在英国法庭上，大家都要以圣经的名义发誓讲实话，或者说是swear by the book. By the book后来就延伸为遵守规矩、照章办事的意思了。
例句：He insists on doing everything by the book.（他坚持一切照章办事。）