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Nowadays, more and more flyovers can be seen in many parts of big cities, especially in the places where traffic is very h and crossing the road is not safe. These b can make people cross roads safely. Flyovers are used in very much the same w  as zebra crossings(斑马线). They are more efficient, though less convenient because it takes people more time to climb up a lot of s   to cross the road. This is inconvenient especially to the old. When people walk on a flyover, they don’t h up traffic. But when they cross a busy road using a zebra crossing, traffic is broken. That is why so many flyovers are built to help people and keep traffic m  at the same time.
The city government have s  lots of money building these flyovers. For their own s , people should use them instead of r across the road. Old people may find it a little d   climbing up and down the steps. But it is still much safer than walking across the road with all the moving traffic.
Flyovers are very useful. People, both old and young, should always use them. This will k  accidents from happening. It’s good for both the pedestrians(行人) and drivers.