The Yangtze River is the longest river in China and the third longest in the world.
扬子江是中国最长的河流,也是世界第三长河。
The longest ditch in the world, as it was called, 300-and-some-odd miles out to Buffalo.
它被称为世界最长的`运河，距布法罗城300多公里。
It's one of the longest and deepest limestone caves not just in the country but in the world.
它不仅是美国最长最深的石灰岩洞穴之一，也是世界上最长最深的石灰岩洞穴之一。
Among them the Yangtze River is the longest one and the second longest one is the Yellow River.
其中最长的是长江，第二长的是黄河。