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The idiom "out of the question" is used to convey that something is not even a possibility, is completely unfeasible, or is definitively not allowed or considered. Its origin is not precisely documented, but it's a common expression used to emphasize that a particular idea, plan, or action is ruled out from the start, without any chance of happening.

The origin of the idiom "green light" can be traced back to the early 20th century, specifically to the traffic signal system. The use of red, yellow, and green lights in traffic signals was introduced to regulate and control vehicular movement. The green light, being the third and final signal in the sequence, indicated that it was safe for drivers to proceed. This phrase is frequently used in business settings, project management, decision-making processes, and personal endeavors.

The origin of the idiom "dos and don'ts" can be traced back to the early 20th century, where it emerged as a concise way to express a set of guidelines or rules. The phrase is derived from the use of "dos" and "don'ts" as shorthand for "things to do" and "things not to do." It is commonly employed in areas such as etiquette, safety protocols, job training, educational settings, and general life advice.

The origin of the idiom "by the book" draws from the idea of following instructions or guidelines found in a book or manual, which can be traced back to ancient times. This phrase may have gained prominence during the 19th century, as the use of written rules and regulations became more widespread in various fields. It is commonly used in discussions related to law, regulations, policies, and professional practices.