If you have a complex task, you can break it down into a number of subtasks. The original task and its subtasks form a task group. The original task becomes the parent of the group.

To group several tasks together, select them and choose Right-click -> Group. The blue task icon changes to show when a task is a subtask
or the parent
of a task group. Subtasks have their Task descriptions indented.
To hide the subtasks of a group, close the group by clicking on on the Icon of the group's parent task. The icon changes
to show when a group is closed.
To create a new task as a subtask of an existing task, click on New Subtask in the toolbar. You cannot give a subtask to a subtask.
To make an existing task become a subtask of another task, drag it onto its new parent. To make a task join an existing group, drag it into the group.
To remove a task from a group, right-click on it and choose Ungroup. To turn a whole group back into normal tasks, ungroup the parent task.
The parent of a task group cannot be made a subtask in another group.
Sorting
When you sort your task list, all of the member of a group are kept together, if the parent of the group is visible. If you want the subtasks to be sorted in the same order as the overall task list, choose Menu->View->Sort Subtasks. Otherwise you can drag the subtasks into whichever order you want.
Repeating groups and subtasks.
If the parent of a task group is set to repeat, what happens to its subtasks when you complete it? That depends on the repeat settings of the subtasks.
| • | Subtasks with no repeat are not carried forward to the next version of the parent task. |
| • | Subtasks set to Repeat With Parent are carried forward, and their dates are adjusted by the same amount as the parent task. |
| • | Subtasks with other repeat settings are carried forward but their dates are not changed. |
What if you complete a subtask?
| • | Subtasks set to Repeat With Parent are set to Completed. But they don't repeat until the parent task is completed. |
| • | Subtasks with other repeat settings are repeated according to those settings. They stay in the same group. |
| • | Subtasks with no repeat settings are completed, with no repeat and no carry forward. |
Subtasks and Toodledo
If you are syncing TaskAngel with Toodledo, to use Groups Subtasks you need a Toodledo Pro account. If you don't have one, TaskAngel's Groups and Subtasks will still work, and you can still sync with Toodledo. But if you use Toodledo to change a subtask, it will be taken out of whatever group it was in.