To learn a language it is not enough to know a maximum of vocabulary otherwise one could learn the dictionaries of languages ​​and to be persuaded that one knows this or that language. To affirm to know a language it is imperative to master its grammar that is to say the rules that manage the functioning of this language. Once mastered, grammar allows us to understand, to express ourselves orally or in writing and to be perfectly understood. It is through grammar that I propose to my students to tackle a language in order to learn and master it.