a network of railroads的用法和样例：
- Asian nations have agreed to form a network of railroads that aims to connect 28 countries in the region to each other and Europe.
- Under the mountain there is a network of caves.
- The company has a network of shops all over the country.
- The fabrics are merchandised through a network of dealers.
- Bangkok is crisscrossed by a network of klongs.
- The city is dissected by a network of old canals.