The phrase "leaves undone" often refers to tasks or responsibilities that are not completed. Synonyms for this phrase could include "neglected," "abandoned," "overlooked," "forgotten," "unattended," "unfinished," "undone," "left behind," "unmanaged," and "undealt with." These words not only describe tasks that have not been completed, but they also highlight the sense of neglect or failure that often accompanies unfinished work. Whether it's a project, household chore, or personal responsibility, choosing the right synonym can help convey the appropriate level of urgency or importance for getting it done.