The motor vehicle has killed and disabled more people in its brief history than any bomb or weapon ever invented．Much of the blood on the street flows essentially from uncivil behavior．of drivers who refuse to respect the legal and moral rights of others．So the massacre(大屠杀) on the road may be regarded as a social problem．In fact, the enemies of society on wheels are rather harmless people, just ordinary people acting carelessly, you might say．But it is a principle both of law and common morality that carelessness is no excuse when one's actions could bring death or damage to others.
Researchers have estimated that as many as 80 percent of all automobile accidents can be attributed to the psychological condition of the driver．Emotional upsets can distort drivers'reactions, slow their judgments, and blind them to ers that might otherwise be evident．The experts warn that it is vital for every driver to make a conscious effort to keep one's emotions under control.
Yet the irresponsibility that accounts for much of the problem is not confined to drivers．Street walkers regularly violate traffic regulations．They are at fault in most vehicle walker accidents．And many cyclists even believe that they are not subject to the basic rules of the road.
Significant legal advances have been made towards safer driving in the past few years．Safety standards for vehicle have been raised both at the point of manufacture and through periodic road-worthiness inspections．In addition, speed limits have been lowered．Due to these measures, the accident rate has deceased．But the accident experts still worry because there has been little or no improvement in the way drivers behave．The only real and lasting solution, say the experts, is to convince people that driving is a skilled task requiring constant care and concentration．Those who fail to do all these things present a threat to those with whom they share the roadside.
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