You need to be on the ULTIMATE plan or the PRO plan with the "Subtasks" feature selected.
In WEEK PLAN, a task can have multiple subtasks. A subtask has all the features of a task, including the ability to have subtasks. (WEEK PLAN supports unlimited levels of subtasks).
Subtasks are a great way to break down a bigger task into more manageable smaller tasks.
In a list view, tasks will show the next subtask, as well as a counter of the remaining subtasks to complete:
You can add more subtasks by editing a task and selecting the "Checklist" tab.
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