Web services are loosely-coupled and self descriptive applications. They are based on standards such as SOAP for message transport, WSDL for service description, and UDDI for service advertisement and discovery. Nevertheless, the lack of semantics in WSDL prevents automatic discovery and hence automatic invocation and composition. In our work, we are interested in extending existing approaches for the description of Semantic Web Services. Our proposed approach, Yet Another Semantic Annotation for WSDL (YASA4WSDL), is an extension of the W3C recommendation on semantics for Web services (SAWSDL) and use two types of ontologies: a Technical Ontology type containing concepts defining semantics of services, their QoS... and a Domain Ontology type containing the concepts defining the semantics of the business domain. We present how our approach is more expressive than the W3C recommendation and submissions to W3C on semantics of Web Services. We show via our implementation how to automatically generate from YASA4WSDL, descriptions like SAWSDL, OWL-S, or WSMO