help!!!

What is different between " made from" and "made of" ?

Made of： 你可以看得出來這樣東西的材質，比如：This cup is made of plastic. 杯子是塑料做的，一目了然。

Made from （初始原料）： 你無法輕易看出這樣東西的初始原料，比如：Paper is made from cotton or hay. 你很難從紙張本身看出它究竟是用棉花還是稻草做的，所以用 made from。再如: Many types of synthetic textile are made from petroleum. 很多種人造纖維是從石油中提煉的化學品製造的，但是你看見的是布，很難把它直接與石油聯繫起來，於是就該用 made from。