In TMetric, tasks can have two statuses: Open and Completed. Open tasks are pending tasks, whereas Completed tasks are those that are already done.
After you finish the task, it acquires a Completed status. To complete a task, open the task editor and click the Mark Complete icon on the required task or the tick icon next to the task name. A completed task will disappear from the list of open tasks. You can see it by setting the Status filter to Completed.
You can reopen the task by clicking the Completed icon or the green tick icon next to the task name.
A completed task can be edited, the changes will be reflected in all the time entries associated with the task.