Secondly, a language is a living organism that evolves through its speakers. Advanced textbooks introduce students to contemporary idioms and regional variations that reflect a nation's current social climate. Without an appreciation for the history and culture behind these expressions, a student remains a "mechanical" speaker. Engaging with authentic materials—such as those found in the Exprès series—bridges the gap between the classroom and the real world, allowing learners to adopt a more natural, fluid style of communication.

For years, the textbook has been a cornerstone of higher education in French-language preparatory courses, particularly for students in Classes Préparatoires aux Grandes Écoles (CPGE) , law school, and political science institutes. Known in full as "Express: Dictionnaire des notions en culture générale et expression" (11th edition), this book is the bible for mastering the highly competitive French essay exam.