man-made polymer

例句：

1. 1. The man-made diamond is more valuable than the natural one.
   人造钻石比天然钻石更值钱。
2. 2. The man-made bridge was built to replace the old wooden one.
   这座人造桥是为了取代旧木桥而建的。
3. 3. The man-made city is a symbol of modern architecture.
   这个人造城市是现代建筑的象征。