这是什么做的?/ 这是什么组成的?
例子：A:Good morning.what can i do for you?
B:Yes,i'd like a blue hat.
A:Ok,here it is.
B:It is made of cotton?
A:No .it isn;t
B:Oh.What is it made of?
A:It's made of wool
B:I see.thank you