In a manner which adheres strictly to rules, legal requirements, or official procedures.(phrase)
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Use "by the book" in a sentence
"The following year I added a program inspired by the book Jonathan Livingston Seagull by Richard Bach."
"I knew George the Fourth's physician, Sir William Knighton, who had been mine before I was imprisoned (it was not he who was the royal agent alluded to); and, if my memory does not deceive me, Sir William told me that George had been gratified by the book above mentioned."
"A major example is James Thomson's ex - traordinarily popular The Seasons (1730-46) in which the divine analogy of “God” offered by the book of"