Contextual Graphs are a context-based formalism used in various real-world applications. They allow a uniform representation of elements of reasoning and of contexts for describing different human tasks such as diagnosis and interpretation. The representation of reasoning by Contextual Graphs supposes an efficient representation of the knowledge associated with a reasoning. Extending the previous view of (1) context relative to a focus, and (2) context as composed of external knowledge and contextual knowledge, in this paper we go a step further by proposing a description of the focus in terms of the instantiation of the contextual elements, which are drawn from domain knowledge. We present the results of this study in a real-world application that we are working on currently, namely the self-evaluation of drivers' behaviors in a situation presented within a large spectrum of contexts.