Since we couldn't live at the bottom of the sea or on the mountain tops, we lived on fluvial or littoral terraces, where we could use the sea and rivers while keeping a safe distance from them.
我們沒有本事在海底或高山上生活，再加上地殼每逢幾千幾百年就要變動作怪，所以就只好挑土質較佳；不受海浪河流影響，又可充分利用海洋和河川資源的海階及河階居住。