Please report dangerous drivers to the police - Roadsafe. Report to plod, not just whinge here.

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147
Be considerate. Be careful of and considerate towards all types of road users, especially those requiring extra care (see Rule 204). You should

try to be understanding if other road users cause problems; they may be inexperienced or not know the area well
be patient; remember that anyone can make a mistake
not allow yourself to become agitated or involved if someone is behaving badly on the road. This will only make the situation worse. Pull over, calm down and, when you feel relaxed, continue your journey
slow down and hold back if a road user pulls out into your path at a junction. Allow them to get clear. Do not over-react by driving too close behind to intimidate them
do not throw anything out of a vehicle, for example, cigarette ends, cans, paper or carrier bags. This can endanger other road users, particularly motorcyclists and cyclists.