The bicycle is one of the simplest yet most useful inventions in the world. What is most surprising is that it was not invented earlier, although the great artist Leonardo Da Vinci had drawn a picture for bicycles and also for flying machines and some other things. Those things were not produced(制造) until long after he died.
A person riding a bicycle uses very little energy(能量) to make the bicycle move, and there is no pollution at all when you are riding. Even so, in developed countries, most people don’t travel to work by bicycle. It is not because the bicycles are expensive or people feel tired if they ride to work. It’s because the number of cars on the road becomes larger. It certainly becomes more dangerous to ride a bicycle. As a result, more people put their bicycles away and go to work in their cars and in this way, the situation(情况) is made more serious. perhaps the best way to make riding safer and more popular is to create(修建) paths only for bicycles, and to make it so difficult and expensive for drivers to take their cars into the city that they will go back to use their bicycles.
