Castles are usually enormous structures requiring strong foundations and the use of heavy construction materials such as stone.

一般来说，城堡是巨大的建筑物，需要打下夯实的地基和使用如石头般坚固的材料。

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The foundations of the city walls were decorated with every kind of precious stone.

城墙的根基是用各样宝石修饰的。

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These valleys were densely populated in pre-European times and you will see low, stone temples and groups of long-abandoned traditional house foundations.

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