The trench is most sharply defined on the eastern (continental) side: depth plunges rapidly from a few hundred meters (light blue) to several thousand meters (deep blue).

海沟最明显的界限是东部靠大陆的地方：海水深度突然从两三百米（浅蓝色）迅速降低到数千米（深蓝色）。

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The typical trench system in World War I consisted of a series of two, three, four, or more trench lines running parallel to each other and being at least 1 mile (1.6 km) in depth.

第一次世界大战时典型的堑壕体系由2至4条以至更多的一系列壕沟组成，壕沟之间彼此平行，而且纵深可以达到1英里（合1.6公里）。

youdao

By 1918 the Germans had constructed some trench systems that had a depth of 14 miles (22 km).

1918年时，德军已经建造了一些纵深达到14英里(和22公里)的堑壕体系。

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Their commentary may have cultural force in the mainstream media, but it often lacks the sedimentary depth accrued by serious trench work in the history of ideas, science and technology, or philosophy.

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