(2) As can be seen from the figure, the Shanghai-Kunming line from Shanghai to Kunming is parallel to the Yangtze River;
(3) As can be seen from the figure, among the east-west trunk lines of China's railways, the longest is the Longhai-Lanxin line, which runs from Lianyungang to Lanzhou, and Lianyungang is the bridgehead of the eastern section of the Second Eurasian Continental Bridge;
(4) As can be seen from the figure, the easternmost longitudinal railway line in China is the Beijing-Shanghai line from Beijing to Shanghai, which intersects with the Beijing-Guangzhou railway line, the longest east-west trunk line, in Xuzhou.
(5) The Qinghai-Tibet Railway is the highest plateau railway in the world, and its completion has ended the history of no railway in Xizang Autonomous Region;
(6) From Beijing to Kunming by train, choose the best route, which can be from Beijing along the Beijing-Guangzhou line via Changsha to Zhuzhou, along the Hunan-Guizhou line to Guiyang, and then along the Guikun line to Kunming.
So the answer is: (1) Beijing-Shanghai; Jingjiu; Jingguang; Liu Jiao; (2) Shanghai-Kunming line; (3) Longhai-Lanxin Line; Lianyungang; (4) Beijing-Shanghai line; Xuzhou; (5) Qinghai-Tibet; High; Xizang Autonomous Region; (6)