You should be able to use safety-related controls without losing attention on the road.
The examiner expects you to know controls such as indicators, lights, wipers, demisters and heaters and to operate them correctly when needed.
These examples are for understanding and practice; they are not a promise that a particular mistake will always receive a particular grade.
Looking down for too long while searching for a control.
Failing to use demisters or lights appropriately when conditions require them.