Open sunken courtyard diagram

Quick answer：

A sunken courtyard, also known as a sunken garden, is a landscape design feature where the courtyard is lower than the surrounding ground level. This creates a sense of seclusion and privacy. The diagram would typically show the layout of the courtyard, including architectural elements such as walls, steps, and pathways, as well as natural features like plants, water bodies, and lighting fixtures. This type of design is often used in traditional Chinese gardens to enhance the overall aesthetic and create a tranquil environment.