be made of和be made from 都是“用……制成”的意思,介詞of和from都可以表示一件制成的東西所用的原料,但兩者在用法上是有區(qū)別的.
be made of 表示制成成品后,仍可看出原材料是什么,保留原材料的質(zhì)地形狀,制作過程僅發(fā)生了物理變化.be made from 表示制成的東西完全失去了原材料的外形或特征,或原材料在制作過程中發(fā)生了化學(xué)變化,在成品中已無法辨認(rèn).試比較：
① The desks and chairs are made of wood.這些課桌椅是木材制成的.
②The ink bottles are made of glass.墨水瓶是玻璃制成的.
③ Salt is made from sea water.鹽是用海水制成的.
④ This kind of wine is made from wheat.這種酒是用小麥制成的.
⑤ Books are made of paper and paper is made from wood.書是紙制成的,而紙是用木材制成的