修改如下,仅供参考：
Every year,thousands of people visit the city Venice.It's very beautiful.
There is no road ,so there are no cars,buses and taxis either.
There are canals only.All of them add to 178 and one of them is quite big while the rest are small.People move up and down the canals with boats.Venice is sinking now.It was said that in 2040 Venice might be under the water.The sea called Adriatic will cover it.