Résumé
Successful communication requires loads of various knowledge including peoples' habits to express their thoughts. We deal here with the description of objects composing a scene. This is called 'reference generation', a task very frequently performed in language production. The skill of language production requires at least two kinds of competencies: one dealing with the mapping of concepts to forms (linguistic competency), the other dealing with the choice of the various resources (communicative competency). Messages can be expressed in many ways and at various levels: lexical, grammatical, morphological, etc. Since different means tend to produce different effects, students have to learn when to use which. This kind of knowledge, commonly called 'pragmatic knowledge' or 'communicative competency', can rarely be formalized as solid rules. It is largely based on experience. People learn on the basis of correlations, that is they realize that changes of the situation may reflect in language: different inputs (ideas, objects of a scene) yielding different outputs, i.e. linguistic forms. We present here a setting that allows for this kind of learning. It is a web-based application that generates a scene and various descriptions of its components. Users can change the scene and watch how these choices affect (or not) the linguistic form. The descriptions are produced in two languages (English and French), and they are rated in terms of communicative adequacy. This should allow students not only to learn how to produce correct sentences, but also help them to realize which one of them is, communicatively speaking, the most adequate form.