Four concrete walls.

四面混泥土墙。

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Four concrete walls of different lengths act as a divisions between different areas within the building and support the thick, flat roof - a contrast to the Alpstein peaks that rise behind it.

四个不同长度的混凝土墙作为建筑不同区域的分离，并支撑又厚又平的屋顶——与后面升起的阿尔卑斯山峰形成对比。

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The house has four bedrooms, a big garden, sea views and a 300-square-feet cavern with 32-inch thick concrete walls.

这所房子有四件卧室，一个花园，可以观看海景和一个面积为8千多米的地下洞穴，四周水泥墙壁厚达80多厘米(见上图)。

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With more than a hundred accredited diplomats, Iran's embassy in Managua - a massive compound surrounded by four-meter-high concrete walls lined with razor wire - is one of the largest diplomatic compounds in the world.

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Sitting behind his oversized desk in a fortress-like compound surrounded by reinforced concrete blast walls and protected by four separate security gates, Gen.

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