Besides events, PERT also knows activities and sub-activities: PERT activity: the actual performance of a task which consumes time and requires resources (such as labor, materials, space, machinery).
除了事件PERT還具有活動和子活動： PERT活動：此為任務的實際績效，將消耗時間並且需要資源（如勞動力、材料、空間、機械）。