The soldiers were digging trenches.

士兵们(那时)正在挖战壕。

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Under a blazing sun, farmers were digging trenches in Nizhny Novgorod on Sunday to stop wildfires in nearby forests and peat bogs from advancing on their land.

周日，下诺夫哥罗德，农民正在烈日下挖沟，阻挡来自附近森林和泥炭沼的山火，蔓延到自己的耕地。

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Eircom would cut its work force by outsourcing a lot of what it had been doing, such as digging trenches and laying cables.

FORBES: The Irish way

Eduardo had a year in the army, digging trenches in the unlikely event that with war nearing its end the Germans would invade.

ECONOMIST: Obituary

They worked 14-hour days, seven days a week - six days producing munitions in the factory and the seventh digging trenches for the approaching front.

BBC: Wartime slave labourers tell their stories