The paper is made of wood.一般纸不是看不见原材料吗?为什么用of?还是这是特殊用法?

Paper is made from the wood of trees.
纸是由树木制成的.
Most of the work is made from wood and paper.
作品的材料主要来源于木材和纸张
The paper for books and newspapers is also made of wood.
用来印刷书报的纸张也是由木材做的.
be made of 和 be made from 是怎么用的 你自己看看例句吧