【正确答案】Nowadays more and more people live in cities. As a result, there is a big traffic, but there are not usually enough roads, and many of the roads are too narrow. That is why there are a lot of traffic accidents. Among the cities all over the world thousands of people are killed or hurt in traffic accidents. Of course, traffic accidents may happen outside cities in the countryside, but there is not so much traffic, so there are not so many accidents.
Why do accidents happen? Some people say that it is the fault of the people who use the roads. That means everybody! If everyone is careful, there will be no accidents. Do you agree?
Other people say that we must improve our roads. "Improve" means "make better". We improve roads by making them wider and straighter. Accidents often occur on roads or in corners. Drivers cannot see around corners. They cannot see other vehicles coming towards them. Therefore, they sometimes crash into each other. When roads are improved, corners are changed. The road does not turn very quickly, but bends slowly. Do you know what a "bend" refers to?
Accidents also happen on the crossing in the roads. There are usually traffic lights there. The traffic lights stop the cars in one road and let the cars in the other go on, which avoids them crashing into each other. Sometimes there is a policeman instead of traffic lights on the crossing. On some occasion, roads do not cross, instead, one road goes above the other. If you pass through there in a bus, you may feel that you are flying over the road below.