translation.en: So I was thinking, but when you look at the past, the way to understand the past is only by the traces available, because we cannot go back [to] the past.
translation.zh: 所以我想， 当你回首过去， 去理解过去的方法， 只有沿着留下的痕迹去追寻。 因为 过去已如泥沙沉淀。