These knives are made ( ) metal and wood?
问题描述：
These knives are made ( ) metal and wood?
from?of?by?in?
答
of （小刀是用金属和木头做成的,可以看的出来）
make of 的原材料是看的到的,比如make of wood
make from的原材料是看不到的,比如Paper is make from trees.从纸上是看不出一棵树滴．