Web service interactions have triggered the initiative to identify and solve mismatches from a behavioral aspect. Current approaches are limited since they mainly focus on control-flow but largely ignore data-flow. In this paper, we propose an approach to automatically generate scenarios and views for describing external behavior of Web services, i.e. the public process, considering both control-flow and data-flow. We define a scenario as a set of complete execution paths for a public process. Data dependencies are presented as a dependency graph, which is optimized into a minimal dependency graph. Then, a view is generated to describe a scenario for analysis purposes, and external behavior of a Web service is described as a finite set of views. Our approach is very useful for service modelers and users to better understand the external behavior of Web services, to identify and solve mismatches from a behavioral aspect, and thus to facilitate Web service interactions.