Sometimes they are forced to skirt the concrete machine gun emplacements of Iranian border guards, at others they have to wade across freezing mountain streams or negotiate sheer precipices.

有时，他们被迫绕过伊朗边防军的混凝土机枪阵地，有时，他们不得不趟过寒冷的山涧溪流或绕过峻峭的悬崖。

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As for whether the concrete and steel bridge towers needed to be 300 meters-breaking yet another record-sometimes the most responsible engineers can get a little carried away.

至于混凝土和钢制的桥塔都要超过300米——这又打破了一项记录——有时候最可靠的工程师也会感到有点头晕目眩。

youdao

Sometimes a type name is used in an instance document, such as when the type of a concrete element is specified with xsi: type.

有时候类型名称在一个实例文档中使用，比如当用xsi： type指定一个具体元素的类型时。

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But I'll tell you, having been on the receiving end of information sometimes which one could constitute as, 'warnings, ' they are often difficult to act on, sometimes not very concrete.

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Sometimes they have a more concrete goal.

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It is sometimes used in combination with modern materials like reinforced concrete or steel for building houses and bridges.

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