We introduce, in this article, a way for building a Virtual Environment for Training to manage dynamic and collaborative situations in team sport. In these situations, relevant information can not be totally known in advance. Autonomous agents can only reason with few pieces of information and explanations on the situation are numerous and not easily predictable. We introduce, in this paper, the usefulness of the notion of context, in a VET, to set up agent decision-making and to generate explanations in order to help the learner. The main purpose of this article is that the context is a medium facilitating information reuse.