Enlisted personnel are identified by way of their various 'E' grades ranging from E-1 to E-9. For those service branches recognizing a Warrant Officer rank, 'W' grades range from W-1 to W-5. Likewise Officers are scaled from O-1 to O-10.
China has quite a collection of natural bridges, including one that experts say has the longest span of any natural bridge in the world. The Fairy Bridge (Xianren Qiao), in southwestern China's Guangxi Zhuang Autonomous Region near the border with Vietnam, has a 400-foot span.
Xianren Bridge, also known as Fairy Bridge, in Guangxi, China is currently the world's largest known natural bridge with a span recorded at 400 feet (120 m) by the Natural Arch and Bridge Society in October 2010, with a precision of Â±15 feet (4.6 m).he Natural Arch and Bridge Society identifies a bridge as a subtype of arch that is primarily water-formed. By contrast, the Dictionary of Geological Terms defines a natural bridge as a natural arch that spans a valley of erosion..