题目内容：

be made of 和 be made up of有什么区别
桥由石头制成,是用be made of 还是 be made up of
为什么?
请用be made up of举例

优质解答

be made of指看得出原料的,如The bridge is made of stones.be made from指看不出原料的,如Paper is made from wood.be made up of更强调由一组里的某些部分构成,如Our class is made up of 50 students....