VOA慢速英语:3D Printers Are Here—And They Make More Than You Think

例句：These seeds must be covered with a layer of earth.
      这些种子必须盖上一层泥土。

2.additive a.添加的
n. 添加物,加法

例句：The orange juice contains a number of additives.
      这种桔子汁含有多种化学添加剂。

3.manufacture vt.(大规模)制造；生产
 
例句：It is manufactured by hand.
      这是手工制造的。

4.prosthetic adj.修复的; 弥补性的

5.artificial adj.人造的, 人工的, 假的

例句：The new dam will form a large artificial lake behind it.
      新筑的水坝将会在后面形成一个人工湖。

6.combine vt.vi.(使)联合, 结合, 组合, 混合

7.kit n.成套用品

例句：This furniture comes as a kit.
      这是一套组合家具。