The researchers stacked up these layers, plus a few more, into a tidy little square.

研究人员将这些层叠加起来，再加上几层，形成一个整洁的小方块。

Extruding the cement through a tube and stacking several layers on top of each other using a 3D printer made a tiny, stable wall.

通过管子挤出水泥， 并使用 3D 打印机将几层水泥层层叠叠， 制成一堵微小而稳定的墙。