If an attribute depends on only part of a multi-valued key, then remove it to a separate table.
如果一个属性仅依赖于一个多重主键的一部分，则将该属性转移到一个单独的表中。
2
The key point of the part is how the suburb employment centers promote the formation of the multi-central metropolitan area as well as how they cause the central cities feebly.
这部分论述的重点是郊区就业中心是如何促进多中心的大都市区的形成以及如何导致中心城市的衰弱。
3
The pump consists of prime motor, multi stage centrifugal pump, seat, wire and control, in which the keypart is the prime motor.