According to this principle, things shall be done in order of priority and the following is the sort of tasks per its priority
A. Important and urgent tasks (such as fire fighting, rescue, etc.) must be done immediately
B. Important and not urgent tasks (such as learning, making plan, etc.) couldn’t be delayed and should be done as urgent things as long as there are no tasks in the sort of “A” that is important and urgent.
C. Urgent and not important tasks (for instance, there is someone suddenly call you for shopping or dinner right row, etc.) need to be done when the important things are finished. It is common for some people set emergency tasks as the priority, rather than the important tasks. In fact, it is not important to do some things that seem urgent.
D. Neither urgent nor important tasks (such as entertainment, recreation, etc.) could be done in one’s spare time