be made of 就是这种东西是用什么做的,是能看的出原材料的;
be made from 是指用什么做的,但是看不出原材料的;
BE MADE BY 是指通过谁或者什么方式做出来的,比如,MADE BY HAND/MACHINE/SOMEBODY;
BE MADE IN 是在哪里生产的,MADE IN CHINA,HOLLAND ETC.