2. Ships sailing; A boat [boat] sails, and so does a boat. -"Guang Yun" voyage, the ark also. Ben Zuo -"Ji Yun" thought it was a ship and a column beam. -Huai Nan Zi Zhu Shu is like a river without navigation. -"Zhang Hengchuan" long whale swallowed the ship. -"Selected Works of Zuo Du Fu" is another example: the boatman (boatman) merged with two ships, and the [pontoon bridge] was formed by connecting ships. Such as: bridge (bridge) aviation, aircraft flight activities [aviation]. Such as: civil aviation navigation (mobile) ships; Navigation Today, airplanes, spaceships and other aircraft flying in the air are also called navigation. Such as: aviation; Aerospace; The shipping industry (the business of ships carrying goods or passengers in and out of the port) is very nervous, so it is impossible to cross the [cross] canyon, so it is impossible to sail. -"Travel Notes of Xu Xiake"