English idiom · neutral · spoken & written · BrE & AmE
an open book: meaning and examples
an open book means a person whose thoughts and feelings are easy to understand.
Aprende la expresión como una unidad fija y observa la preposición y la forma verbal en los ejemplos.
این عبارت را بهصورت یک واحد ثابت یاد بگیرید و به حرف اضافه و شکل فعل در مثالها توجه کنید.
Lerne die Wendung als feste Einheit und achte in den Beispielen auf Präposition und Verbform.
Apprenez l’expression comme une unité fixe et observez la préposition et la forme verbale dans les exemples.
Memory hook: Build a clear mental picture from “an open book” and connect it to this meaning: a person whose thoughts and feelings are easy to understand.
How to use “an open book”
- Ask me anything — I’m an open book.
- His face is an open book.
Common mistake: Treat “an open book” as a fixed expression. Notice its exact word order in the examples.
Learn it in context
This expression belongs to Lesson 11, where you can compare it with other idioms about character and practise it interactively.
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