The decision-making process is the most important step in the translation steps, whether in the grammar or semantic aspect. This research deals with this step in its grammar aspect, as it studies the decision-making process in translating actual structures from Arabic into English as one of the translation steps. The research proposes a practical decision-making mechanism in the legal systems related to the actual structures, including time, body and act building. On the theoretical side, the research provides a brief introduction on the subject and in the field of work. It provides an application of this mechanism to samples for translations of some students of the fourth stage in the translation department, then gives the results and conclusions of the research and suggests some recommendations.