The Requirement Engineering is the first and one of the most critical phases of any software development methodology. This phase is very complex because of the imprecision of the process, the communication problems and the different viewpoints of the stakeholders. Requirements defined with imprecision or ambiguity hide and/or make difficult the discovery of the different interactions that could exist between requirements. These requirements are considered interdependent, as one requirement depends on or affect others. The identification of the interactions between the requirements allows understanding and acting on the impact of these interactions in the subsequent stages of the software development process. There are several methods for requirements specification. However, most of them don't show explicitly these interactions. In this paper, we present an approach that allows the specification, identification and revealing the different interactions between requirements, using a semi-formal method based on events. The events are considered because the flows of events describe the behavior of the system, through a set of interactions between objects.