“be made of”和“be made from”的使用对象不同：be made of表示制成成品后，仍可看出原材料是什么，保留原材料的质和形状，制作过程仅发生物理变化。be made from表示制成的东西完全失去了原材料的外形或特征，或原材料在制作过程中发生化学变化，在成品中已无法辨认。

be made of和be made from对比

The kite is made of paper.风筝是用纸做的。（能看出原材料）

The paper is made from wood.纸是木头做的。（看不出原材料）

be made of例句

The pipes should be made of plastic.

这些管子应该是用塑料制作的。

The taps appeared to be made of solid gold.

水龙头似乎是用纯金制成的。

Only the rough guess and estimate can be made of it.

对此只能作出一个粗略的测算。

be made from例句

There's money to be made from tourism.

旅游业非常有利可图。

An unlimited number of copies can still be made from the original

仍可以由原件复印出无数份副本来。

Synthetic silk can be made from wood fibres.

人造丝可用木纤维制造。