The paper presents selected problems of visualizing animated sign language sentences in real time. The presented solution is a part of a system for translation of texts into the sign language. The animation and graphical techniques applied in the system are briefly presented, but the main problems discussed are: how to specify the sign language and how to interpret such a specification. A concise, easy-to-use Szczepankowski's gestographic notation has been adopted. It is widely used in the Polish deaf community. It has been originally intended to be used by humans; thus a part of information it holds is incomplete, inexact, in many cases highly intuitive. The automatic interpretation has to reconstruct all the information that lacks. Another group of problems we have encountered involves issues of kinematics: the motion is to be generated depending on the information that is very general. Techniques like reverse kinematics and collision detecting and avoiding have to be applied. In effect the system is capable to demonstrate gestures as well as whole sentences on the basis of the notation, that is easy for humans to create and to read