The phrase "sits on" implies an object or person resting or leaning on something else. There are various synonyms that can be used to describe this action, such as perching, resting, reclining, leaning, propping, and sitting upon. Each of these synonyms has a slightly different nuance and can be used to convey a specific image or feeling. For example, "perching" might suggest a bird sitting on a tree branch, while "leaning" could imply someone resting against a wall. By using different synonyms for "sits on", writers can add depth and variety to their language, creating a richer and more engaging text.