It's a reference to the barriers that built up between the band members over the years and everyone's desire to tear down the obstacles and heal old scars.

其实这句歌词寓意很深，暗示着乐队这几年来遇到的不少障碍，乐队的成员们都渴望着能拔掉这些钉子，让旧日的伤口早日愈合。

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The idea behind biological acne scarring treatment is that old, damaged tissues and scars are replaced by new cells.

生物学中痤疮疤痕的治疗方法是用新细胞代替旧的受损组织及疤痕。

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The old trapper's hut beneath Singing Mountain bears the scars of an unwelcome visitor.

在辛宁山脚下的狩猎人小屋被不速之客弄得伤痕累累。

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The far closer working relationship between the Foreign Office and the Quai d'Orsay established in 1991 with the break-up of Yugoslavia has meant that the old scars from the failed collaboration over Suez in 1956 have largely healed.

ECONOMIST: Yes to Europe, No to federalism | The

And the 31-year-old Sydney Roosters veteran insists the scars have yet to heal.

BBC: Aussies driven by fear of failure

The scars on his knees, which Ito is letting Simpson exhibit, would presumably illustrate how old football injuries would have hindered his ability to overpower two people and stab them to death.

CNN: O.J. Simpson trial: Opening statements; testimony begins