分析一下这条定语从句的句子成份An important factor in a market-oriented econ
分析一下这条定语从句的句子成份
An important factor in a market-oriented economy is the mechanism by which consumer demands can be expressed and responded to by producers ,我想问介词in加带词which怎么理解,为什么是in而不是其他介词..还原一下定语从句啦.谢谢