Humanoid robots are required to perform a wide repertoire of tasks working beside humans in complex dynamic environments. Learning mechanisms are important for building up these types of repertoires of robot skills. However, despite the clear advantages of these approaches, it would be impractical to teach the robot skills for every needed task and for every foreseen situation. Robot skills learning approaches to develop humanoid robotic systems would have greater impact if the models of the skills can be operated upon to generate new behaviors of increasing levels of complexity. A framework that allows the adaptation of previously learned motion skills to new unseen contexts is necessary. In this work, we present different modalities for the adaptation and generation of new skill models based on the already learned models of the skills. Experimental results are presented to validate this approach.