First of all you should sit and start to tell your boyfriend that you are affraid about his high speed driving. You should tell him about your feelings and fears. Try to convince him that high speed driving can end up in a very bad way, also try to give him as much examples of high speed driving which ended up with car crash. If he wouldn't listen to you, than try to talk to his relatives for them to convince him.
hello my dear. High speed can cause many deaths. Every day we can read that someone get in the accident. Just imagine, that in one year 1.25 mln people die in the accident (most of them are motocyclists and pedestrians). you can show him this statistic and tell, that it can be he or you. We aren't insured, that some car will hit us. The horrible thing can happen, if your boyfriend will hit some person. Speak with him about consequences. I think he will understand that you care about him abd agree, that fast speed is very dangerous.
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