修建
7.The construction or operation of railroads.
1.Ramps were built and extended around the pyramid and used as the road to drag up the blocks. When the pyramid was done, they took the ramps away. Susan, do you know who built the pyramid?
金字塔周围修建了一些斜坡.人们顺着坡道把巨石拖上去.随着金字塔高度的增加.斜坡也越来越长.等金字塔建好了.再把坡道拆掉.苏珊.你知道金字塔是谁建的吗?


