Car accidents happen everywhere every day and are the main cause of injury in the United States. In order to control the increasing  accidents, many states have passed tough laws. Also, car manufacturers  have been trying to make safer cars to save lives. However, as there are more and more cars and drivers on the road, these safety measure  are not enough to stop the increasing car accidents. The National Highway Traffic Safety Administration  reports that a car accident happens every 10 seconds in the United States. Car accidents may be caused by different reasons. Some accidents are caused by driver's tiredness and illness or drunk driving. Some may be caused by speeding or running a red light. When this happens, by the time the driver realizes what has happened, it is usually too late. As for ages, young drivers usually have enough experience while _ drivers of react slowly. Mechanical defects  such as a broken brake  are another cause of car accidents. Poor road and weather conditions can also be a cause. Talking about different causes of car accidents can help us know what precautions  to take beforehand. We should tell our friends or family members not to drive in poor health or after drinking wine. We should tell teenager drivers to be careful with road and weather conditions and let elderly friends understand their driving limitation . Besides, we should have our car checked regularly . The most important thing for us to remember, however, is that we should always follow the traffic rules. In order to avoid accidents caused by mechanical defects, we should   _  .
not run a red light. drive the car when we are in good health not drive when we are too old. have our cars examined regularly.