短文首字母填空 (共10小题；每小题l分，满分l0分)
根据短文内容及所给首字母提示写出所缺单词，使短文内容完整。
Overhead bridges can be seen in many parts of Singapore. Overhead bridges are in the places where traffic is very heavy and c_______the road is not safe. These bridges can help people cross roads safely．Overhead bridges are u_______ in very much the same way as zebra crossings．They are more efficient（效率高的），though l________convenient（方便的）because people have to climb up a lot of s________. This is inconvenient to the old．When people use an overhead bridge，they do not hold up traffic．But when they cross a busy road using a zebra crossing，traffic is held up．This is w_____ the government has built many overhead bridges to help people and k ______ traffic moving at the same time. The government of Singapore has saved a lot of  m________ to build these bridges．For their own safety，people should use them i______of rushing across the road．Old people may find it a little difficult, but it is much safer than walking across the road with all the moving t_______．Overhead bridges are very useful. People, both old and young, should always use them．This will stop accidents from h _____．Are there any overhead bridges in your city?